Patent Application
20250172874
The present invention relates to a resist composition, a method for forming a resist pattern, a new compound, and a polymer compound.
Priority is claimed on Japanese Patent Application No. 2022-036436, filed Mar. 9, 2022, the content of which is incorporated herein by reference.
In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, advances in lithography technologies have led to rapid progress in the field of pattern miniaturization. These pattern miniaturization techniques typically involve shortening the wavelength (increasing the energy) of the exposure light source.
Resist materials require lithography characteristics such as a high resolution that enables reproduction of patterns with minute dimensions, and a high level of sensitivity to these kinds of exposure light sources.
As a resist material that satisfies these requirements, a chemically amplified resist composition containing a base material component whose solubility in a developing solution is changed by an action of an acid and an acid generation agent component that generates an acid upon light exposure has been used.
In the chemically amplified resist composition, a resin having a plurality of constitutional units is typically used in order to improve lithography characteristics and the like.
For example, Patent Document 1 suggests a resist composition containing a resin which has two kinds of repeating units having a specific structure and whose solubility in an alkali developing solution is increased by an action of an acid.
Patent Document 1: Japanese Unexamined Patent Application, First Publication No. 2006-276759
With the further progress of the lithography technology and resist pattern fining, for example, it is aimed to form a fine pattern with a size of several tens of nanometers in lithography by EUV and EB. In this manner, with further miniaturization of a pattern, a decrease in film thickness of a resist film has proceeded, and thus a resist material is required to have further improved etching resistance in a case where etching is performed by using a resist pattern as a mask. Further, the resist material is required to have high sensitivity to radiation as miniaturization of the pattern proceeds. With respect to these required characteristics, resist compositions of the related art are required to have further improved performance.
The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a resist composition capable of further enhancing etching resistance and achieving high sensitivity, a method for forming a resist pattern using the resist composition, a polymer compound useful for the resist composition, and a compound useful for producing the polymer compound.
In order to achieve the above-described object, the present invention employs the following configurations.
That is, according to a first aspect of the present invention, there is provided a resist composition which generates an acid upon light exposure and whose solubility in a developing solution is changed by an action of the acid, the resist composition including: a resin component (A1) whose solubility in a developing solution is changed by an action of an acid, in which the resin component (A1) has a constitutional unit (a0) derived from a compound represented by General Formula (a0-1).
[In Formula (a0-1), W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. RaO1 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
According to a second aspect of the present invention, there is provided a method for forming a resist pattern, including: a step of forming a resist film on a support using the resist composition according to the first aspect; a step of exposing the resist film to light; and a step of developing the resist film exposed to light to form a resist pattern.
According to a third aspect of the present invention, there is provided a compound which is represented by General Formula (a0-1).
[In Formula (a0-1), W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
According to a fourth aspect of the present invention, there is provided a polymer compound including a constitutional unit derived from a compound represented by General Formula (a0-1).
[In Formula (a0-1). W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
According to the present invention, it is possible to provide a resist composition capable of further enhancing etching resistance and achieving high sensitivity, a method for forming a resist pattern using the resist composition, a polymer compound useful for the resist composition, and a compound useful for producing the polymer compound.
In the present specification and the scope of the present claims, the term “aliphatic” is a relative concept used in relation to the term “aromatic”, and defines a group, a compound, or the like that has no aromaticity.
The term “alkyl group” includes a linear, branched, or cyclic monovalent saturated hydrocarbon group unless otherwise specified. The same applies to the alkyl group in an alkoxy group.
The term “alkylene group” includes a linear, branched, or cyclic divalent saturated hydrocarbon group unless otherwise specified.
Examples of “halogen atom” include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
The term “constitutional unit” indicates a monomer unit constituting a polymer compound (a resin, a polymer, or a copolymer).
The expression “may have a substituent” includes both a case where a hydrogen atom (—H) is substituted with a monovalent group and a case where a methylene (—CH2—) group is substituted with a divalent group.
The term “light exposure” is a general concept for irradiation with radiation.
The term “base material component” denotes an organic compound having a film-forming ability. Organic compounds used as the base material component are classified into non-polymers and polymers. As the non-polymers, those having a molecular weight of 500 or greater and less than 4000 are typically used. Hereinafter, the term “low-molecular-weight compound” denotes a non-polymer having a molecular weight of 500 or greater and less than 4000. As the polymer, those having a molecular weight of 1000 or greater are typically used. Hereinafter, “resin”, “polymer compound”, or “polymer” indicates a polymer having a molecular weight of 1000 or greater. As the molecular weight of the polymer, the weight-average molecular weight in terms of polystyrene according to gel permeation chromatography (GPC) is used.
The expression “constitutional unit to be derived” denotes a constitutional unit formed by cleavage of a multiple bond between carbon atoms, for example, an ethylenic double bond.
In “acrylic acid ester”, the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent. The substituent (Rαx) that substitutes the hydrogen atom bonded to the carbon atom at the α-position is an atom other than the hydrogen atom or a group. Further, the acrylic acid ester includes itaconic acid diester in which the substituent (Rαx) has been substituted with a substituent having an ester bond and α-hydroxyacryl ester in which the substituent (Rαx) has been substituted with a hydroxyalkyl group or a group obtained by modifying a hydroxyl group thereof. Further, the carbon atom at the α-position of acrylic acid ester indicates the carbon atom to which the carbonyl group of acrylic acid is bonded, unless otherwise specified.
Hereinafter, acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α-position has been substituted with a substituent is also referred to as α-substituted acrylic acid ester.
The concept “derivative” includes those obtained by substituting a hydrogen atom at the α-position of a target compound with another substituent such as an alkyl group or a halogenated alkyl group, and derivatives thereof. Examples of the derivatives thereof include those obtained by substituting a hydrogen atom of a hydroxyl group of a target compound, in which the hydrogen atom at the α-position may be substituted with a substituent, with an organic group, and those obtained by bonding a substituent other than a hydroxyl group to a target compound in which the hydrogen atom at the α-position may be substituted with a substituent. Further, the α-position denotes the first carbon atom adjacent to a functional group unless otherwise specified.
Examples of the substituent that substitutes the hydrogen atom at the α-position of hydroxystyrene include those for Rαx.
In the present specification and the present claims, asymmetric carbons may be present and enantiomers or diastereomers may be present depending on the structures of the chemical formulae. In this case, these isomers are represented by one chemical formula. These isomers may be used alone or in the form of a mixture.
The resist composition according to the first aspect of the present invention is a resist composition that generates an acid upon light exposure and whose solubility in a developing solution is changed by the action of the acid.
The resist composition according to the embodiment contains a base material component (A) (hereinafter, also referred to as “component (A)”) whose solubility in a developing solution is changed by the action of the acid.
In a case where a resist film is formed using the resist composition according to the present embodiment and the formed resist film is subjected to selective exposure, an acid is generated at exposed portions of the resist film, and the generated acid acts on the component (A) to change the solubility of the component (A) in a developing solution. On the other hand, the solubility of the component (A) in a developing solution is not changed at unexposed portions of the resist film, which generates the difference in solubility in the developing solution between exposed portions and unexposed portions of the resist film.
The resist composition of the present embodiment may be a positive-tone resist composition or a negative-tone resist composition.
Further, in the formation of a resist pattern, the resist composition according to the present embodiment can be applied to an alkali developing process using an alkali developing solution in the developing treatment, or a solvent developing process using an organic developing solution in the developing treatment.
That is, the resist composition according to the present embodiment is a “positive-tone resist composition for an alkali developing process” that forms a positive-tone resist pattern in an alkali developing process, and a “negative-tone resist composition for a solvent developing process” that forms a negative-tone resist pattern in a solvent developing process.
In the resist composition according to the present embodiment, the component (A) contains a resin component (A1) (hereinafter, also referred to as “component (A1)”) whose solubility in a developing solution is changed by the action of an acid, and the component (A1) has a constitutional unit (a0) derived from a compound represented by General Formula (a0-1).
As the component (A), at least the component (A1) is used, and at least other polymer compound and a low-molecular-weight compound may be used in combination with the component (A1).
In the resist composition according to the present embodiment, the component (A) may be used alone or in combination of two or more kinds thereof.
The component (A1) has a constitutional unit (a0) derived from a compound represented by General Formula (a0-1).
The component (A1) may have, in addition to the constitutional unit (a0), constitutional units other than the constitutional unit (a0).
<<Constitutional Unit (a0)>>
The constitutional unit (a0) is a constitutional unit derived from a compound represented by General Formula (a0-1).
In such a constitutional unit (a0), Ra0 in Formula (a0-1) represents an acid dissociable group, and this acid dissociable group protects the oxy group (—O—) side of the carbonyloxy group [—C(═O)—O)—] in Formula (a0-1).
Here, “acid dissociable group” has acid dissociability, which means a bond between the acid dissociable group and an oxygen atom (an oxy group (—O—)) adjacent to the acid dissociable group can be cleaved by the action of an acid. In a case where the acid dissociable group is dissociated by the action of an acid, a polar group (carboxy group) having a polarity higher than that of the acid dissociable group is generated, and thus the polarity is increased. As a result, the polarity of an entire component (A1) is increased. Due to the increase in the polarity, the solubility of the component (A1) in a developing solution is relatively changed such that the solubility is increased in a case where the developing solution is an alkali developing solution and the solubility is decreased in a case where the developing solution is an organic developing solution.
[In Formula (a0-1), W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Root and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Rate being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
In Formula (a0-1), W01 represents a polymerizable group-containing group.
The term “polymerizable group” as W01 denotes a group that enables a compound containing a polymerizable group to be polymerized by radical polymerization or the like, which is a group having a multiple bond between carbon atoms, such as an ethylenic double bond.
In the constitutional unit (a0), the multiple bond in the polymerizable group are cleaved to form a main chain.
Examples of the polymerizable group as W01 include a vinyl group, an allyl group, an acryloyl group, a methacryloyl group, a fluorovinyl group, a difluorovinyl group, a trifluorovinyl group, a difluorotrifluoromethylvinyl group, a trifluoroallyl group, a perfluoroallyl group, a trifluoromethylacryloyl group, a nonylfluorobutylacryloyl group, a vinyl ether group, a fluorine-containing vinyl ether group, an allyl ether group, a fluorine-containing allyl ether group, a styryl group, a vinylnaphthyl group, a fluorine-containing styryl group, a fluorine-containing vinylnaphthyl group, a norbornyl group, a fluorine-containing norbornyl group, and a silyl group.
The term “polymerizable group-containing group” as W01 may denote a group formed of only a polymerizable group or a group formed of a polymerizable group and a group other than the polymerizable group. Examples of the group other than the polymerizable group include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom.
Divalent Hydrocarbon Group which May have Substituent:
In a case where the group other than the polymerizable group represents a divalent hydrocarbon group which may have a substituent, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
Aliphatic Hydrocarbon Group as a Group Other than the Polymerizable Group
The aliphatic hydrocarbon group indicates a hydrocarbon group that has no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated. In general, it is preferable that the aliphatic hydrocarbon group is saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group having a ring in the structure thereof.
The linear aliphatic hydrocarbon group has preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [—CH2—], an ethylene group [—(CH2)2—], a trimethylene group [—(CH2)3-], a tetramethylene group [—(CH2)4—], and a pentamethylene group [—(CH2)5—].
The branched aliphatic hydrocarbon group has preferably 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples thereof include alkylalkylene groups, for example, alkylmethylene groups such as —CH(CH3)—, —CH(CH2)CH3)—, —C(CH3)2—, —C(CH3)(CH2CH3)—, —C(CH3)(CH2CH2CH3)—, and —C(CH2CH3)2—; alkylethylene groups such as —CH(CH3)CH2—, —CH(CH3)CH(CH3)—, —C(CH3)2CH2—, —CH(CH)CH3)CH2—, and —C(CH)CH3)2—CH2—; alkyltrimethylene groups such as —CH(CH3)CH2CH2— and —CH2CH(CH3)CH2—; and alkyltetramethylene groups such as —CH(CH3)CH2CH2CH2— and —CH2CH(CH3)CH2CH2—. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.
The above linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms which has been substituted with a fluorine atom, and a carbonyl group.
Examples of the aliphatic hydrocarbon group having a ring in the structure thereof include a cyclic aliphatic hydrocarbon group which may have a substituent having a heteroatom in the ring structure thereof (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring), a group in which the cyclic aliphatic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The cyclic aliphatic hydrocarbon group has preferably 3 to 20 carbon atoms and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms have been removed from a polycycloalkane is preferable. As the polycycloalkane, a group having 7 to 12 carbon atoms is preferable. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and most preferably a methoxy group or an ethoxy group.
Examples of the halogen atom for the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which some or all hydrogen atoms in the above-described alkyl groups have been substituted with the above-described halogen atoms.
In the cyclic aliphatic hydrocarbon group, some carbon atoms constituting the ring structure thereof may be substituted with a substituent having a heteroatom. As the substituent having a heteroatom, —O—, —C(═O)—O—, —S—, —S(═O)2—, or —S(═O)2—O— is preferable.
Aromatic Hydrocarbon Group as Group Other than the Polymerizable Group
The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
The aromatic ring is not particularly limited as long as the aromatic ring is a cyclic conjugated system having (4n+2) π electrons and may be monocyclic or polycyclic. The aromatic ring has preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Here, the number of carbon atoms in a substituent is not included in the number of carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some carbon atoms constituting the above-described aromatic hydrocarbon rings have been substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.
Specific examples of the aromatic hydrocarbon group include a group (an arylene group or a heteroarylene group) obtained by removing two hydrogen atoms from the above-described aromatic hydrocarbon ring or the above-described aromatic heterocyclic ring; a group obtained by removing two hydrogen atoms from an aromatic compound (for example, biphenyl or fluorene) having two or more aromatic rings; and a group (for example, a group obtained by further removing one hydrogen atom from an aryl group in the arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group) obtained by substituting one hydrogen atom of a group (an aryl group or a heteroaryl group) obtained by removing one hydrogen atom from the above aromatic hydrocarbon ring or the above aromatic heterocyclic ring, with an alkylene group. The above-described alkylene group bonded to the aryl group or heteroaryl group has preferably 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and particularly preferably 1 carbon atom.
In the aromatic hydrocarbon group, the hydrogen atom in the aromatic hydrocarbon group may be substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of substituents include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the alkoxy group, the halogen atom, and the halogenated alkyl group as the substituents include those described as the substituent that substitutes a hydrogen atom in the cyclic aliphatic hydrocarbon group.
In a case where the group other than the polymerizable group is a divalent linking group having a heteroatom, preferred examples of the linking group include —O—, —C(═O)—O—, —C(═O)—, —O—C(═O)—O—C(═O)—NH—, —NH—, —NH—C(═NH)— (H may be substituted with a substituent such as an alkyl group, an acyl group, or the like, —S—, —S(═O)2—, —S(═O)2—O—, and a group represented by General Formula: —Y21—O—Y22—, —Y21—O—, —Y21—C(═O)—O—, —C(═O)—O—Y21—, —[Y21—C(═O)—O]m″—Y22—, —Y21—O—C(═O)—Y22— or —Y21—S(═O)2—O)—Y22. [in the formulae, Y21 and Y22 each independently represent a divalent hydrocarbon group which may have a substituent. O represents an oxygen atom, and m″ represents an integer of 0 to 3].
In a case where the divalent linking group having a heteroatom is-C(═O)—NH—, —C(═O)—NH—C(═O)—, —NH—, or —NH—C(═NH)—, H may be substituted with a substituent such as an alkyl group or acyl. The substituent (an alkyl group, an acyl group, or the like) has preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
In General Formula —Y21—O—Y22—, —Y21—O—, —Y21—C(═O)—O—, —C(═O)—O—Y21—, —[Y21—C(═O)—O]m″—Y22—, —Y21—O—C(═O)—Y22—, or —Y2—S(═O)2—O—Y22—. Y21 and Y22 each independently represent a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same groups as those for the divalent hydrocarbon group which may have a substituent, described in the section of the divalent linking group above.
Y21 represents preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or an ethylene group.
Y22 represents preferably a linear or branched aliphatic hydrocarbon group and more preferably a methylene group, an ethylene group, or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by Formula —[Y21—C(═O)—O]m″—Y22—, m″ represents an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 1. That is, a group represented by Formula —Y21—C(═O)—O—Y22— is particularly preferable as the group represented by Formula —[Y21—C(═O)—O]m″—Y22—. Among these, a group represented by Formula —(CH2)a′—C(═O))—O—(CH2)b′— is preferable. In the formula, a′ represents an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1. b′ represents an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, still more preferably 1 or 2, and most preferably 1.
It is suitable that W01 represents, for example, a group represented by Chemical Formula: C(RX11)(RX12)═C(RX13)—Yax0-.
In the chemical formula, RX11, RX12, and RX13 each represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Yax0 represents a single bond or a divalent linking group.
The alkyl group having 1 to 5 carbon atoms as RX11, RX12, and RX13 is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all hydrogen atoms in the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable.
Among these, RX11 and RX12 each represent preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, more preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom.
In addition, RX13 represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, more preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom.
The divalent linking group as Yax0 is not particularly limited, and suitable examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom, each of which has the same definition as that for the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, described as groups other than the polymerizable group represented by W01.
Among the examples, it is preferable that Yax0 represents an ester bond [—C(═O)—O— or —O—C(═O)—], an ether bond (—O—), a linear or branched alkylene group, an aromatic hydrocarbon group, or a combination thereof, or a single bond.
Among these, Yax0 represents more preferably an ester bond [—C(═O)—O— or —O—C(═O)—] or a single bond and still more preferably a single bond.
In Formula (a0-1), RAr represents an aromatic group which may have a substituent.
Examples of the aromatic group as RAr include a group in which two hydrogen atoms have been removed from an aromatic ring which may have a substituent. The aromatic ring is not particularly limited as long as the aromatic ring is a cyclic conjugated system having (4n+2) π electrons. The aromatic ring has preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and an aromatic heterocyclic ring obtained by substituting some carbon atoms constituting the above-described aromatic hydrocarbon ring with a heteroatom. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.
Further, examples of the aromatic group as RAr also include a group in which two hydrogen atoms have been removed from an aromatic compound (for example, biphenyl or fluorene) having two or more aromatic rings which may have a substituent.
The aromatic group as RAr may or may not have a substituent. Examples of the substituent include an alkyl group, a halogen atom, a halogenated alkyl group, an alkoxy group, and a hydroxy group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the halogen atom for the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which some or all hydrogen atoms in the above-described alkyl groups have been substituted with the above-described halogen atoms.
An alkoxy group having 1 to 6 carbon atoms is preferable as the alkoxy group serving as the substituent. Further, it is preferable that the alkoxy group is linear or branched. Specific examples thereof include a group in which an alkyl group having 1 to 6 carbon atoms and an oxygen atom (—O—) are linked. Among these, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group is preferable, a methoxy group or an ethoxy group is more preferable, and a methoxy group is still more preferable.
From the viewpoint of enhancing the sensitivity, an alkoxy group or a hydroxy group is preferable, and a hydroxy group is particularly preferable as the substituent.
The number of the substituents that the aromatic group as RAr has is determined depending on the structure of the aromatic group and is, for example, an integer of 0 to 3, preferably 0, 1, or 2, and more preferably 0 or 1.
Among the examples, RAr represents preferably a group in which two hydrogen atoms have been removed from benzene, naphthalene, anthracene, or biphenyl, which may have a substituent, more preferably a group in which two hydrogen atoms have been removed from benzene which may have a substituent or a group in which two hydrogen atoms have been removed from naphthalene which may have a substituent, and still more preferably a group in which two hydrogen atoms have been removed from benzene which may have a substituent.
Alternatively, from the viewpoint of enhancing the sensitivity, RAr represents preferably an aromatic group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and more preferably an aromatic group having a hydroxy group as a substituent. Among these, a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from benzene, naphthalene, anthracene, or biphenyl is more preferable, a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from benzene or a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from naphthalene is still more preferable, a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from benzene is particularly preferable, and a group having a hydroxy group as a substituent and obtained by removing two hydrogen atoms from benzene is most preferable.
In Formula (a0)-1), Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). In Formula (a0-r-1), * represents a bonding site with respect to an oxy group (—O—) to which Rat is bonded.
From the viewpoint of enhancing the sensitivity, it is preferable that Ra0 represents a chain-like group.
From the viewpoint of etching resistance, it is preferable that Ra0 represents a cyclic group.
In Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group.
Examples of the aliphatic hydrocarbon group as Ra01 include a linear or branched hydrocarbon group. Among these, a linear hydrocarbon group is preferable. Here, the linear or branched hydrocarbon group has preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and still more preferably 1 to 4 carbon atoms.
Specific examples of the linear or branched alkyl group as Ra01 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Among these, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a tert-butyl group is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is still more preferable.
In Formula (a0-r-1), Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent or a hydrogen atom.
The hydrocarbon group as Ra02, Ra03, and Ra04 is preferably an aliphatic hydrocarbon group and may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, but a saturated aliphatic hydrocarbon group is more preferable.
Examples of the saturated aliphatic hydrocarbon group as Ra02, Ra03, and Ra04 include a linear, branched, or cyclic alkyl group.
Examples of the linear or branched alkyl group as Ra02, Ra03, and Ra04 include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Among these, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, or a tert-butyl group is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is still more preferable.
Examples of the cyclic alkyl group as Ra02, Ra03, and Ra04 include an alicyclic group having 3 to 20 carbon atoms. The alicyclic group may be a monocyclic group or a polycyclic group.
Examples of the monocyclic alicyclic group include a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 10 carbon atoms, more preferably has 4 to 8 carbon atoms, and still more preferably has 5 or 6 carbon atoms. Specific examples of the monocycloalkane include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, and cyclooctane. Among these, cyclopentane or cyclohexane is preferable.
Examples of the polycyclic alicyclic group include a group obtained by removing one hydrogen atom from a polycycloalkane. The polycycloalkane preferably has 7 to 15 carbon atoms, more preferably has 7 to 12 carbon atoms, and still more preferably has 7 to 10 carbon atoms. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Examples of the substituent that the hydrocarbon group as Ra02, Ra03, and Ra04 may have include an alkyl group, a halogen atom, and a halogenated alkyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the halogenated alkyl group as the substituent include groups in which some or all hydrogen atoms in the above-described alkyl groups have been substituted with the above-described halogen atoms.
Among the examples, Ra02, Ra03, and Ra04 each independently represent preferably a linear or branched alkyl group or a hydrogen atom and more preferably a linear alkyl group or a hydrogen atom.
In Formula (a0-r-1). Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Examples of the alicyclic structure formed by Ra01 and Ra02 include an alicyclic group having 3 to 20 carbon atoms. The alicyclic group may be a monocyclic group or a polycyclic group and is preferably an alicyclic group having 5 to 15 carbon atoms. Preferred examples thereof include a cyclopentenyl group and a cyclohexenyl group. Among these, a cyclopentenyl group is more preferable.
Some carbon atoms constituting the alicyclic structure may be substituted with heteroatoms. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Here, from the viewpoint of acid dissociation properties, a carbon atom is bonded to a tertiary carbon atom bonded to an oxy group (—O—) in Ra01.
In Formula (a0-r-1), Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure.
The aromatic ring structure formed by Ra03 and Ra04 has preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Specific examples of the aromatic ring include an aromatic hydrocarbon ring such as benzene, naphthalene, anthracene, or phenanthrene; and an aromatic heterocyclic ring in which some carbon atoms constituting the above-described aromatic hydrocarbon ring are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom.
Examples of the alicyclic structure formed by Ra03 and Ra04 include the same structures as those for the alicyclic structure formed by Ra01 and Ra02 described above.
Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other.
In Formula (a0-r-1), suitable examples of Ra01, Ra02, Ra03, and Ra04 include a case where Ra01 represents a linear hydrocarbon group and all of Ra02, Ra03, and Ra04 represent a hydrogen atom; a case where Ra03 and Ra04 are bonded to each other to form an aromatic ring structure; and a case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure.
Suitable examples of the case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure include a case where Raff and Ra02 are bonded to each other to form an alicyclic structure and Ra03 and Ra04 each represent a linear or branched alkyl group or a hydrogen atom; and a case where the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure formed by Ra03 and Ra04 being bonded to each other are condensed to form a condensed ring structure.
Particularly from the viewpoint of enhancing the sensitivity, it is preferable that Ra01, Ra02, Ra03, and Ra04 represent a chain-like group, and suitable examples thereof include a case where Ra01 represents a linear hydrocarbon group and all of Ra02, Ra03, and Ra04 represent a hydrogen atom.
Particularly from the viewpoint of the etching resistance, it is preferable that Ra01, Ra02, Ra03, and Ra04 represent a cyclic group, and suitable examples thereof include a case where Ra03 and Ra04 are bonded to each other to form an aromatic ring structure and a case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure.
In Formula (a0-r-1), Ra05 represents a chain-like or alicyclic hydrocarbon group, or a hydrogen atom.
Examples of the chain-like hydrocarbon group as Ra05 include a linear or branched saturated hydrocarbon group (alkyl group) and a linear or branched unsaturated hydrocarbon group.
Specific examples of the linear or branched alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.
More specific examples of the unsaturated hydrocarbon group in the linear or branched unsaturated hydrocarbon group include an unsaturated hydrocarbon group having a double bond, such as an alkenyl group, an alkadienyl group, or an alkatrienyl group; and an unsaturated hydrocarbon group having a triple bond, such as an alkynyl group, a group in which one hydrogen atom has been removed from a dialkyne, or a group in which one hydrogen atom has been removed from a trialkyne.
Specific examples of the linear or branched alkenyl group include a linear alkenyl group such as a vinyl group, a propenyl group (an allyl group), or a 2-butenyl group; and a branched alkenyl group such as a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, or 2-methylpropenyl group.
Specific examples of the alkadienyl group include a propadienyl group and a butadienyl group.
Specific examples of the alkatrienyl group include a butatrienyl group.
Specific examples of the linear or branched alkynyl group include a linear alkynyl group such as an ethynyl group, a propargyl group, or a 3-pentynyl group; and a branched alkynyl group such as a 1-methylpropargyl group.
Specific examples of the group obtained by removing one hydrogen atom from the dialkyne include a group obtained by removing one hydrogen atom from diacetylene.
Specific examples of the group obtained by removing one hydrogen atom from the trialkyne include a group obtained by removing one hydrogen atom from hexa-1,3,5-triyne.
Specific examples of the alicyclic hydrocarbon group as Ra05 include a monocyclic alicyclic group and a polycyclic alicyclic group.
The monocyclic alicyclic group is preferably a group obtained by removing one hydrogen atom from a monocycloalkane or a monocycloalkene. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The monocycloalkene preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentene and cyclohexene.
The polycyclic alicyclic group is preferably a group obtained by removing one hydrogen atom from a polycycloalkane or a polycycloalkene. The polycycloalkane preferably has 7 to 12 carbon atoms, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. In addition, the polycycloalkene is preferably a group having 7 to 12 carbon atoms. Specific examples thereof include adamantene, norbornene, isobornene, tricyclodecene, and tetracyclododecene.
In Formula (a0-r-1), it is preferable that Ra05 represents a linear or branched saturated hydrocarbon group (alkyl group) or a hydrogen atom.
From the viewpoint of the etching resistance, it is preferable that Ra05 represents a hydrogen atom.
From the viewpoint of the sensitivity, it is preferable that Ra05 represents a chain-like or alicyclic hydrocarbon group.
Among the examples described above, it is preferable that the constitutional unit (a0) is a constitutional unit represented by General Formula (a0-1-u0).
[In the formula, Rm represents an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. L1 represents a divalent linking group or a single bond. Ra06 represents a hydrogen atom or an alkyl group, m represents an integer of 0 to 3, n represents an integer of 0 or greater. Here, n≤4+2m is satisfied. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
In Formula (a0-1-u0), Rm represents an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom.
The alkyl group having 1 to 5 carbon atoms as Rm is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.
The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all hydrogen atoms in the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom is particularly preferable as the halogen atom in the halogenated alkyl group.
Rm represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms and, from the viewpoint of industrial availability, most preferably a hydrogen atom or a methyl group.
In Formula (a0-1-u0), L1 represents a divalent linking group or a single bond.
The divalent linking group as L1 is not particularly limited, and suitable examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom, each of which has the same definition as that for the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, described as groups other than the polymerizable group represented by W01.
Among these, it is preferable that L1 represents an ester bond [—C(═O)—O— or —O—C(═O)—], an ether bond (—O—), a linear or branched alkylene group, an aromatic hydrocarbon group, or a combination thereof, or a single bond. Among the examples, L1 represents more preferably an ester bond [—C(═O)—O— or —O—C(═O)—] or a single bond and still more preferably a single bond.
In Formula (a0-1-u0), Ra06 represents a hydrogen atom or an alkyl group.
The alkyl group as Ra06 is preferably an alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group, and still more preferably a methyl group or an ethyl group.
In Formula (a0-1-u0), m represents an integer of 0 to 3. A benzene structure is formed in a case where m represents 0, a naphthalene structure is formed in a case where m represents 1, an anthracene structure is formed in a case where m represents 2, and a tetracene structure is formed in a case where m represents 3.
In Formula (a0-1-u0), n represents an integer of 0 or greater, preferably an integer of 1 to 5, more preferably an integer of 1 to 3, and still more preferably 1 or 2.
Here, n≤4+2m is satisfied.
In Formula (a0-1-u0), Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.
Ra01, Ra02, Ra03, Ra04, and Ra05 in Formula (a0-r-1) each have the same definition as described above.
In Formula (a0-r-1), suitable examples of Ra01, Ra02, Ra03, and Ra04 include a case where Ra01 represents a linear hydrocarbon group and all of Ra02, Ra03, and Ra04 represent a hydrogen atom; a case where Ra03 and Ra04 are bonded to each other to form an aromatic ring structure; and a case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure.
Suitable examples of the case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure include a case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure and Ra03 and Ra04 each represent a linear or branched alkyl group or a hydrogen atom; and a case where the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure formed by Ra03 and Ra04 being bonded to each other are condensed to form a condensed ring structure.
Specific examples of the constitutional unit (a0) are as follows.
In the formulae shown below, Rα represents a hydrogen atom, a methyl group, or a trifluoromethyl group.
In the resist composition according to the present embodiment, the constitutional unit (a0) is preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formulae (a0-1-u1) to (a0-1-u9), constitutional units each represented by Chemical Formulae (a0-1-u10) to (a0-1-u18), constitutional units each represented by chemical Formulae (a0-1-u19) to (a0-1-u24), constitutional units each represented by Chemical Formulae (a0-1-u25) to (a0-1-u28), constitutional units each represented by chemical Formulae (a0-1-u29) to (a0-1-u32), constitutional units each represented by Chemical Formulae (a0-1-u33) to (a0-1-u38), and constitutional units each represented by Chemical Formulae (a0-1-u39) to (a0-1-u44) and, among these, more preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formulae (a0-1-u1) to (a0-1-u9), constitutional units represented by Chemical Formulae (a0-1-u10) to (a0-1-u18), constitutional units each represented by Chemical Formulae (a0-1-u19) to (a0-1-u24), and constitutional units each represented by Chemical Formulae (a0-1-u39) to (a0-1-u44).
Alternatively, from the viewpoint of enhancing the sensitivity, the constitutional unit (a0) is preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formula (a0-1-u1), Chemical Formula (a0-1-u10), Chemical Formula (a0-1-u19), Chemical Formula (a0-1-u25), Chemical Formula (a0-1-u29), Chemical Formula (a0-1-u33), and Chemical Formula (a0-1-u39); more preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formula (a0-1-1), Chemical Formula (a0-1-u10), and Chemical Formula (a0-1-u19); and still more preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formula (a0-1-u1) and Chemical Formula (a0-1-u10).
From the viewpoint of the etching resistance, the constitutional unit (a0) is preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formulae (a0-1-u2) to (a0-1-u9), constitutional units each represented by Chemical Formulae (a0-1-u11) to (a0-1-u18), constitutional units each represented by Chemical Formulae (a0-1-u20) to (a0-1-u24), constitutional units each represented by Chemical Formulae (a0-1-u26) to (a0-1-u28), constitutional units each represented by Chemical Formulae (a0-1-u30) to (a0-1-u32), constitutional units each represented by Chemical Formulae (a0-1-u34) to (a0-1-u38), and constitutional units each represented by Chemical Formulae (a0-1-u40) to (a0-1-u44); more preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formulae (a0-1-u2) to (a0-1-u9), constitutional units each represented by Chemical Formulae (a0-1-a11) to (a0-1-u18), constitutional units each represented by Chemical Formulae (a0-1-u20) to (a0-1-u24), and constitutional units each represented by Chemical Formulae (a0)-1-u40) to (a0-1-u44); and still more preferably at least one selected from the group consisting of constitutional units each represented by Chemical Formulae (a0-1-u2) to (a0-1-u9), constitutional units each represented by Chemical Formulae (a0-1-u11) to (a0-1-u18), and constitutional units each represented by Chemical Formulae (a0-1-40) to (a0-1-u44).
The constitutional unit (a0) of the component (A1) may be used alone or in combination of two or more kinds thereof.
The proportion of the constitutional unit (a0) in the component (A1) is preferably 20% by mole or greater and 80% by mole or less, more preferably 30% by mole or greater and 70% by mole or less, and still more preferably 40% by mole or greater and 65% by mole or less with respect to the total amount (100% by mole) of all constitutional units constituting the component (A1).
In a case where the proportion of the constitutional unit (a0) is greater than or equal to the lower limits of the above-described preferable ranges, both the sensitivity and the etching resistance are likely to be enhanced. Meanwhile, in a case where the proportion of the constitutional unit (a0) is less than or equal to the upper limits of the above-described preferable ranges, the constitutional unit (a0) and other constitutional units are likely to be balanced.
<<Other Constitutional Units in Addition to Constitutional Unit (a0)>>
The component (A1) may have other constitutional units as necessary in addition to the constitutional unit (a0) described above.
Examples of other constitutional units include a constitutional unit (a1) containing an acid decomposable group whose polarity is increased by the action of an acid; a constitutional unit (a10) represented by General Formula (a10-1); a constitutional unit (a5) which generates an acid upon light exposure; a constitutional unit (a2) which contains a lactone-containing cyclic group; and a constitutional unit (a8) derived from a compound represented by General Formula (a8-1). Further, constitutional units corresponding to the constitutional unit (a0) described above are excluded from the other constitutional units.
The constitutional unit (a1) is a constitutional unit that contains an acid decomposable group whose polarity is increased by the action of an acid. However, those corresponding to the constitutional unit (a0) described are excluded.
The term “acid decomposable group” indicates a group having acid decomposability in which at least a part of a bond in the structure of the acid decomposable group can be cleaved by the action of an acid.
Examples of the acid decomposable group whose polarity is increased by the action of an acid include groups which are decomposed by the action of an acid to generate a polar group. Examples of the polar group include a carboxy group, a hydroxyl group, an amino group, and a sulfo group (—SO3H).
More specific examples of the acid decomposable group include a group in which the above-described polar group has been protected with an acid dissociable group (such as a group in which a hydrogen atom of the OH-containing polar group has been protected with an acid dissociable group).
Examples of the acid dissociable group are the same as those which have been suggested as the acid dissociable groups of the base resin for a chemically amplified resist composition.
Specific examples of the acid dissociable group of the base resin suggested for a chemically amplified resist composition include “acetal type acid dissociable group”, “tertiary alkyl ester type acid dissociable group”, “tertiary alkyloxycarbonyl acid dissociable group”, and “secondary alkyl ester type acid dissociable group” described below.
Examples of the acid dissociable group that protects a carboxy group or a hydroxyl group among the polar groups include an acid dissociable group represented by General Formula (a1-r-1) (acetal type acid dissociable group).
[In the formula, Ra′1 and Ra′2 each represent a hydrogen atom or an alkyl group. Ra′3 represents a hydrocarbon group. Ra′3 may be bonded to any one of Ra′1 or Ra′2 to form a ring.]
In Formula (a1-r-1), it is preferable that at least one of Ra′1 or Ra′2 represents a hydrogen atom and more preferable that both Ra′1 and Ra′2 represent a hydrogen atom.
In a case where Ra′1 or Ra′2 represents an alkyl group, an alkyl group having 1 to 5 carbon atoms is preferable as the alkyl group. Specific preferred examples thereof include linear or branched alkyl groups. More specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Among these, a methyl group or an ethyl group is more preferable, and a methyl group is particularly preferable.
In Formula (a1-r-1), examples of the hydrocarbon group as Ra′3 include a linear or branched alkyl group and a cyclic hydrocarbon group.
The linear alkyl group has preferably 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and still more preferably 1 or 2 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.
The branched alkyl group has preferably 3 to 10 carbon atoms and more preferably 3 to 5 carbon atoms. Specific examples thereof include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group. Among these, an isopropyl group is preferable.
In a case where Ra′3 represents a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group in which one hydrogen atom has been removed from a monocycloalkane is preferable. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.
As the aliphatic hydrocarbon group which is a polycyclic group, a group in which one hydrogen atom has been removed from a polycycloalkane is preferable. As the polycycloalkane, a group having 7 to 12 carbon atoms is preferable, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
In a case where the cyclic hydrocarbon group as Ra′3 is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
The aromatic ring is not particularly limited as long as the aromatic ring is a cyclic conjugated system having (4n+2) π electrons and may be monocyclic or polycyclic. The aromatic ring has preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms.
Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some carbon atoms constituting the above-described aromatic hydrocarbon rings have been substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.
Specific examples of the aromatic hydrocarbon group as Ra′3 include a group in which one hydrogen atom has been removed from the above-described aromatic hydrocarbon ring or aromatic heterocyclic ring (such as an aryl group or a heteroaryl group); a group in which one hydrogen atom has been removed from an aromatic compound having two or more aromatic rings (such as biphenyl or fluorene); and a group in which one hydrogen atom of the above-described aromatic hydrocarbon ring or aromatic heterocyclic ring has been substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group). The number of carbon atoms in the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocyclic ring is preferably in a range of 1 to 4, more preferably 1 or 2, and particularly preferably 1.
The cyclic hydrocarbon group as Ra′3 may include a substituent.
Examples of the substituent include —RP1, —RP2—O—RP1, —RP2—CO—RP1, —RP2—CO—ORP1, —RP2—O—CO—RP1, —RP2—OH, —RP2—CN, and —RP2—COOH (hereinafter, these substituents will also be collectively referred to as “Rx5”).
Here, RP1 represents a chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms, a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms. Further, RP2 represents a single bond, a chain-like divalent saturated hydrocarbon group having 1 to 10 carbon atoms, a divalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, or a divalent aromatic hydrocarbon group having 6 to 30 carbon atoms.
Here, some or all hydrogen atoms in the chain-like saturated hydrocarbon group, the aliphatic cyclic saturated hydrocarbon group, and the aromatic hydrocarbon group as RP1 and RP2 may be substituted with fluorine atoms. In the aliphatic cyclic hydrocarbon group, one or more of the above-described substituents may be included as a single kind, or one or more of the above-described substituents may be included as a plurality of kinds.
Examples of the chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a decyl group.
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include a monocyclic aliphatic saturated hydrocarbon group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, or a cyclododecyl group; and a polycyclic aliphatic saturated hydrocarbon group such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.02,6]decanyl group, a tricyclo[3.3.1.13,7] decanyl group, a tetracyclo[6.2.1.13,6.02,7] dodecanyl group, or an adamantyl group. Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include a group formed by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, or phenanthrene.
In a case where Ra′3 is bonded to any of Ra′1 and Ra′2 to form a ring, the cyclic group is preferably a 4- to 7-membered ring and more preferably a 4- to 6-membered ring. Specific examples of the cyclic group include a tetrahydropyranyl group and a tetrahydrofuranyl group.
Examples of the acid dissociable group that protects a carboxy group among the polar groups include an acid dissociable group represented by General Formula (a1-r-2).
[In the formula, Ra′4 to Ra′6 each represent a hydrocarbon group, and Ra′5 and Ra′6 may be bonded to each other to form a ring.]
Examples of the hydrocarbon group as Ra′4 include a linear or branched alkyl group, a chain-like or cyclic alkenyl group, and a cyclic hydrocarbon group.
Examples of the linear or branched alkyl group and the cyclic hydrocarbon group (an aliphatic hydrocarbon group which is a monocyclic group, an aliphatic hydrocarbon group which is a polycyclic group, or an aromatic hydrocarbon group) as Ra′4 include the same groups as those for Ra′3.
As the chain-like or cyclic alkenyl group as Ra′4, an alkenyl group having 2 to 10 carbon atoms is preferable.
Examples of the hydrocarbon group as Ra′5 or Ra′6 include the same groups as those for Ra′3.
In a case where Ra′5 and Ra′6 are bonded to each other to form a ring, suitable examples thereof include a group represented by General Formula (a1-r2-1), a group represented by General Formula (a1-r2-2), and a group represented by General Formula (a1-r2-3).
Meanwhile, in a case where Ra′4 to Ra′6 independently represent a hydrocarbon group without being bonded to one another, suitable examples thereof include a group represented by General Formula (a1-r2-4).
[In Formula (a1-r2-1), Ra′10 represents a linear or branched alkyl group having 1 to 12 carbon atoms, in which a part thereof may be substituted with a halogen atom or a heteroatom-containing group. Ra′11 represents a group that forms an aliphatic cyclic group with the carbon atom to which Ra′10 has been bonded. In Formula (a1-r2-2), Ya represents a carbon atom. Xa represents a group that forms a cyclic hydrocarbon group with Ya. Some or all hydrogen atoms in this cyclic hydrocarbon group may be substituted. Ra101 to Ra103 each independently represent a hydrogen atom, a chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms, or a monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms. Some or all hydrogen atoms in the chain-like saturated hydrocarbon group and the aliphatic cyclic saturated hydrocarbon group may be substituted. Two or more of Ra101 to Ra103 may be bonded to each other to form a cyclic structure. In Formula (a1-r2-3), Yaa represents a carbon atom. Xaa represents a group that forms an aliphatic cyclic group with Yaa. Ra104 represents an aromatic hydrocarbon group which may have a substituent. In Formula (a1-r2-4). Ra′12 and Ra′13 each independently represent a chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. Some or all hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted. Ra′14 represents a hydrocarbon group which may have a substituent. * represents a bonding site (the same applies hereinafter).]
In Formula (a1-r2-1), Ra′10 represents a linear or branched alkyl group having 1 to 12 carbon atoms, in which a part thereof may be substituted with a halogen atom or a heteroatom-containing group.
The linear alkyl group as Ra′10 has 1 to 12 carbon atoms, preferably 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
Examples of the branched alkyl group as Ra′10 include those for Ra′3 described above.
The alkyl group in Ra′10 may be partially substituted with a halogen atom or a heteroatom-containing group. For example, some hydrogen atoms constituting the alkyl group may be substituted with a halogen atom or a heteroatom-containing group. Further, some carbon atoms (methylene group or the like) constituting the alkyl group may be substituted with a heteroatom-containing group.
Examples of the heteroatoms here include an oxygen atom, a nitrogen atom, and a sulfur atom. Examples of the heteroatom-containing group include (—O—), —C(═O)—O)—, —O—C(═O)—, —C(═O)—, —O—C(═O)—O—, —C(═O)—NH—, —NH—, —S—, —S(═O)2—, and —S(═O)2—O—.
In Formula (a1-r2-1), preferred examples of Ra′11 (an aliphatic cyclic group that is formed together with a carbon atom to which Ra′10 is bonded) include the groups exemplified as the aliphatic hydrocarbon group (alicyclic hydrocarbon group) which is a monocyclic group or a polycyclic group as Ra′3 in Formula (a1-r-1). Among them, it is preferably a monocyclic alicyclic hydrocarbon group, and specifically, it is more preferably a cyclopentyl group or a cyclohexyl group.
In Formula (a1-r2-2), examples of the cyclic hydrocarbon group that is formed by Xa together with Ya include a group in which one or more hydrogen atoms have been further removed from the cyclic monovalent hydrocarbon group (aliphatic hydrocarbon group) as Ra′3 in Formula (a1-r-1).
The cyclic hydrocarbon group that is formed by Xa together with Ya may have a substituent. Examples of these substituents include the same substituents that the cyclic hydrocarbon group as Ra′3 described above may have.
In Formula (a1-r2-2), examples of the chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms as Ra101 to Ra103 (include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a decyl group.
Examples of the monovalent aliphatic cyclic saturated hydrocarbon group having 3 to 20 carbon atoms as Ra101 to Ra103 include a monocyclic aliphatic saturated hydrocarbon group such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, or a cyclododecyl group; and a polycyclic aliphatic saturated hydrocarbon group such as a bicyclo[2.2.2]octanyl group, a tricyclo[5.2.1.02,6]decanyl group, a tricyclo[3.3.1.13,7] decanyl group, a tetracyclo[6.2.1.13,6.02.7] dodecanyl group, or an adamantyl group.
From the viewpoint of ease of synthesis, Ra101 to Ra103 represent preferably a hydrogen atom or a chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrogen atom, a methyl group, or an ethyl group, and particularly preferably a hydrogen atom.
Examples of the substituent included in the chain-like saturated hydrocarbon group or the aliphatic cyclic saturated hydrocarbon group represented by Ra101 to Ra103 include the same substituents as those for Rax5.
Examples of the group having a carbon-carbon double bond generated by two or more of Ra101 to Ra103 being bonded to each other to form a cyclic structure include a cyclopentenyl group, a cyclohexenyl group, a methylcyclopentenyl group, a methylcyclohexenyl group, a cyclopentylidenethenyl group, and a cyclohexylidenethenyl group. Among these, from the viewpoint of ease of synthesis, a cyclopentenyl group, a cyclohexenyl group, or a cyclopentylidenethenyl group is preferable.
In Formula (a1-r2-3), as the aliphatic cyclic group that is formed by Xaa together with Yaa, the group exemplified as the aliphatic hydrocarbon group which is a monocyclic group or a polycyclic group as Ra′3 in Formula (a1-r-1) is preferable.
In Formula (a1-r2-3), examples of the aromatic hydrocarbon group as Ra104 include a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 5 to 30 carbon atoms. Among the examples, Ra104 represents preferably a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene, or phenanthrene, still more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, or anthracene, particularly preferably a group in which one or more hydrogen atoms have been removed from benzene or naphthalene, and most preferably a group in which one or more hydrogen atoms have been removed from benzene.
Examples of the substituent that Ra104 in Formula (a1-r2-3) may have include a methyl group, an ethyl group, a propyl group, a hydroxyl group, a carboxyl group, a halogen atom, an alkoxy group (a methoxy group, an ethoxy group, a propoxy group, a butoxy group, or the like), and an alkyloxycarbonyl group.
In Formula (a1-r2-4), Ra′12 and Ra′13 each independently represent a chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. Examples of the chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms as Ra′12 and Ra′13 include those exemplified as the chain-like monovalent saturated hydrocarbon group having 1 to 10 carbon atoms as Ra101 to Ra103. Some or all hydrogen atoms in this chain-like saturated hydrocarbon group may be substituted.
Ra′12 and Ra′13 represent preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, still more preferably a methyl group or an ethyl group, and particularly preferably a methyl group.
In a case where the chain-like saturated hydrocarbon group represented by Ra′12 and Ra′13 is substituted, examples of the substituent thereof include the same substituents as those for Rax5.
In Formula (a1-r2-4), Ra′14 represents a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group as Ra′14 include a linear or branched alkyl group and a cyclic hydrocarbon group.
The linear alkyl group as Ra′14 has preferably 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and still more preferably 1 or 2 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.
The branched alkyl group as Ra′14 has preferably 3 to 10 carbon atoms and more preferably 3 to 5 carbon atoms. Specific examples thereof include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group. Among these, an isopropyl group is preferable.
In a case where Ra′14 represents a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group and may be a polycyclic group or a monocyclic group.
As the aliphatic hydrocarbon group which is a monocyclic group, a group in which one hydrogen atom has been removed from a monocycloalkane is preferable. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.
As the aliphatic hydrocarbon group which is a polycyclic group, a group in which one hydrogen atom has been removed from a polycycloalkane is preferable. As the polycycloalkane, a group having 7 to 12 carbon atoms is preferable, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
Examples of the aromatic hydrocarbon group as Ra′14 include the same groups as those for the aromatic hydrocarbon group as Ra104. Among these, Ra′14 represents preferably a group in which one or more hydrogen atoms have been removed from an aromatic hydrocarbon ring having 6 to 15 carbon atoms, more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, anthracene, or phenanthrene, still more preferably a group in which one or more hydrogen atoms have been removed from benzene, naphthalene, or anthracene, particularly preferably a group in which one or more hydrogen atoms have been removed from naphthalene or anthracene, and most preferably a group in which one or more hydrogen atoms have been removed from naphthalene.
Examples of the substituent that Ra′14 may have include the same substituents that Ra104 may have.
In a case where Ra′14 in Formula (a1-r2-4) represents a naphthyl group, the position bonded to the tertiary carbon atom in Formula (a1-r2-4) may be the 1-position or the 2-position of the naphthyl group.
In a case where Ra′14 in Formula (a1-r2-4) represents an anthryl group, the position bonded to the tertiary carbon atom in Formula (a1-r2-4) may be the 1-position, the 2-position, or the 9-position of the anthryl group.
Specific examples of the group represented by Formula (a1-r2-1) are shown below.
Specific examples of the group represented by Formula (a1-r2-2) are shown below.
Specific examples of the group represented by Formula (a1-r2-3) are shown below.
Specific examples of the group represented by Formula (a1-r2-4) are shown below.
Examples of the acid dissociable group that protects a hydroxyl group among the polar groups include an acid dissociable group represented by General Formula (a1-r-3) (hereinafter, also referred to as “tertiary alkyloxycarbonyl acid dissociable group” for convenience).
[In the formula, Ra′7 to Ra′9 each represent an alkyl group.]
In Formula (a1-r-3), Ra′7 to Ra′9 each represent preferably an alkyl group having 1 to 5 carbon atoms and more preferably an alkyl group having 1 to 3 carbon atoms.
Further, the total number of carbon atoms in each alkyl group is preferably in a range of 3 to 7, more preferably in a range of 3 to 5, and most preferably 3 or 4.
Examples of the acid dissociable group that protects a carboxy group among the polar groups include an acid dissociable group represented by General Formula (a1-r-4).
[In the formula, Ra′10 represents a hydrocarbon group. Ra′11a and Ra′11b each independently represent a hydrogen atom, a halogen atom, or an alkyl group. Ra′12 represents a hydrogen atom or a hydrocarbon group. Ra′10 and Ra′11a or Ra′11b may be bonded to each other to form a ring. Ra′11a or Ra′11b and Ra′12 may be bonded to each other to form a ring. * represents a bonding site.]
Examples of the hydrocarbon group as Ra′10 or Ra′12 in Formula (a1-r-4) include the same groups as those for Ra′3.
Examples of the alkyl group as Ra′11a and Ra′11b in Formula (a1-r-4) include the same groups as those for the alkyl group as Ra′1.
In Formula (a1-r-4), the hydrocarbon group as Ra′10 or Ra′12 and the alkyl group as Ra′11a and Ra′11b may have a substituent. Examples of the substituent include Rax5 described above.
Ra′10 and Ra′11a or Ra′11b may be bonded to each other to form a ring.
Ra′11a or Ra11b and Ra′12 may be bonded to each other to form a ring.
The rings that may be formed by these being bonded to each other may each be a polycycle or a monocycle, or may be an alicycle or an aromatic ring. The alicycle and the aromatic ring may have a heteroatom.
Among the examples described above, as the ring (ring (x)) formed by Ra′10 and Ra′11a or Ra′11b being bonded to each other, monocycloalkene, a ring in which some carbon atoms of monocycloalkene have been substituted with heteroatoms (such as an oxygen atom and a sulfur atom), or monocycloalkadiene is preferable, cycloalkene having 3 to 6 carbon atoms is preferable, and cyclopentene or cyclohexene is preferable.
Among the examples described above, as the ring (ring (y)) formed by Ra′11a or Ra′11b and Ra′12 being bonded to each other, an aromatic ring is preferable, and benzene is particularly preferable. The aromatic ring may have a heteroatom, and examples thereof include a thiophene ring.
Alternatively, the ring (x) and the ring (y) may be bonded to each other to form a condensed ring. Specific examples of the condensed ring include indane.
The ring (x), the ring (y), and the condensed ring formed by the ring (x) and the ring (y) being bonded to each other may each have a substituent. Examples of the substituent include Rax5 described above.
Specific examples of the group represented by Formula (a1-r-4) are shown below.
Examples of the constitutional unit (a1) include a constitutional unit derived from acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent; a constitutional unit derived from acrylamide; a constitutional unit in which at least some hydrogen atoms in a hydroxyl group of a constitutional unit derived from hydroxystyrene or a hydroxystyrene derivative are protected by a substituent containing the acid decomposable group; and a constitutional unit in which at least some hydrogen atoms in —C(═O)—OH of a constitutional unit derived from vinylbenzoic acid or a vinylbenzoic acid derivative are protected by a substituent containing the acid decomposable group.
Specific examples of the constitutional unit (a1) are shown below.
In the formulae shown below, Rα represents a hydrogen atom, a methyl group, or a trifluoromethyl group.
The constitutional unit (a1) included in the component (A1) may be used alone or two or more kinds thereof.
In a case where the component (A1) has the constitutional unit (a1), the proportion of the constitutional unit (a1) in the component (A1) is preferably 20% by mole or less and more preferably greater than 0% by mole and less than 20% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the component (A1).
In regard to constitutional unit (a10):
The constitutional unit (a10) is a constitutional unit represented by General Formula (a10-1).
[In the formulae, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Yax1 represents a single bond or a divalent linking group. Wax1 represents an aromatic hydrocarbon group which may have a substituent. nax1 represents an integer of 1 or greater.]
In Formula (a10-1), R represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, more preferably a hydrogen atom, a methyl group, or trifluoromethyl group, still more preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom.
In Formula (a10-1), Yax1 represents a single bond or a divalent linking group. In the chemical formula, the divalent linking group as Yax1 is not particularly limited, and suitable examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom, each of which has the same definition as that for the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, described as groups other than the polymerizable group represented by W01.
Yax1 represents preferably a single bond, an ester bond [—C(═O)—O— or —O—C(═O)—], an ether bond (—O—), a linear or branched alkylene group, or a combination thereof and more preferably a single bond or an ester bond [—C(═O)—O— or —O—C(═O)—].
In Formula (a10-1), Wax1 represents an aromatic hydrocarbon group which may have a substituent.
Examples of the aromatic hydrocarbon group as Wax1 include a group in which (nax1+1) hydrogen atoms have been removed from an aromatic ring which may have a substituent.
The aromatic ring is not particularly limited as long as the aromatic ring is a cyclic conjugated system having (4n+2) π electrons. The aromatic ring has preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms.
Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and an aromatic heterocyclic ring obtained by substituting some carbon atoms constituting the above-described aromatic hydrocarbon ring with a heteroatom. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.
Further, examples of the aromatic hydrocarbon group as Waal also include a group in which (nax1+1) hydrogen atoms have been removed from an aromatic compound having an aromatic ring (for example, biphenyl or fluorene) which may have two or more substituents.
Among the examples, Wax1 represents preferably a group in which (nax1+1) hydrogen atoms have been removed from benzene, naphthalene, anthracene, or biphenyl, more preferably a group in which (nax1+1) hydrogen atoms have been removed from benzene or naphthalene, and still more preferably a group in which (nax1+1) hydrogen atoms have been removed from benzene.
The aromatic hydrocarbon group as Wax1 may or may not have a substituent. Examples of substituents include an alkyl group, an alkoxy group, a halogen atom, and a halogenated alkyl group.
Examples of the alkyl group, the alkoxy group, the halogen atom, and the halogenated alkyl group as the substituent include the same groups described as the substituent of the cyclic aliphatic hydrocarbon group as W01. The substituent is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a linear or branched alkyl group having 1 to 3 carbon atoms, still more preferably an ethyl group or a methyl group, and particularly preferably a methyl group.
It is preferable that the aromatic hydrocarbon group as Wax1 has no substituent.
In Formula (a10-1), nax1 represents an integer of 1 or greater, preferably an integer of 1 to 10, more preferably an integer of 1 to 5, still more preferably 1, 2, or 3, and particularly preferably 1 or 2.
Specific examples of the constitutional unit (a10) represented by Formula (a10-1) are described below.
In the formulae shown below, Ra represents a hydrogen atom, a methyl group, or a trifluoromethyl group.
The constitutional unit (a10) included in the component (A1) may be used alone or two or more kinds thereof.
In a case where the component (A1) has the constitutional unit (a10), the proportion of the constitutional unit (a10) in the component (A1) is preferably in a range of 20% to 80% by mole, more preferably in a range of 30% to 70% by mole, and still more preferably in a range of 35% to 60% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the component (A1).
In a case where the proportion of the constitutional unit (a10) is greater than or equal to the lower limits of the above-described preferable ranges, the sensitivity is likely to be further increased. Meanwhile, in a case where the proportion thereof is less than or equal to the upper limits of the above-described preferable ranges, the constitutional unit (a10) and other constitutional units are likely to be balanced.
In regard to constitutional unit (a5) that generates acid upon light exposure:
In the present embodiment, the constitutional unit (a5) is a constitutional unit which generates an acid upon light exposure, and a known constitutional unit can be used.
Suitable examples of the constitutional unit (a5) include a constitutional unit represented by General Formula (a5-1).
[In the formula, Rm represents an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. La1 represents a divalent linking group or a single bond. Ra050 represents a divalent hydrocarbon group which may have a substituent. La0 represents a divalent linking group. Ya0 represents a divalent linking group which may have a heteroatom or a single bond. Ra051 and Ra052 each independently represent a hydrogen atom, a fluorine atom, or a fluorinated alkyl group. n0 represents an integer of 1 to 4. m represents an integer of 1 or greater, and M′m+ represents an m-valent onium cation.]
In Formula (a5-1), Rm represents an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom.
The alkyl group having 1 to 5 carbon atoms as Rm is preferably a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.
The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all hydrogen atoms in the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom is particularly preferable as the halogen atom in the halogenated alkyl group.
Rm represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms and, from the viewpoint of industrial availability, most preferably a hydrogen atom or a methyl group.
In Formula (a5-1), La1 represents a divalent linking group or a single bond.
The divalent linking group as La1 is not particularly limited, and suitable examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom, each of which has the same definition as that for the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, described as groups other than the polymerizable group represented by W01.
Among these, it is preferable that La1 represents an ester bond [—C(═O)—O— or —O—C(═O)—], an ether bond (—O—), a linear or branched alkylene group, an aromatic hydrocarbon group, or a combination thereof, or a single bond. Among these, La1 represents more preferably an ester bond [—C(═O)—O— or —O—C(═O)—] or a single bond and still more preferably an ester bond [—C(═O)—O— or —O—C(═O)—].
In Formula (a5-1), Ra050 represents a divalent hydrocarbon group which may have a substituent.
The divalent hydrocarbon group as Ra050 may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
Aliphatic hydrocarbon group as Ra050
The aliphatic hydrocarbon group indicates a hydrocarbon group that has no aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated. In general, it is preferable that the aliphatic hydrocarbon group is saturated.
Examples of the aliphatic hydrocarbon group include a linear or branched aliphatic hydrocarbon group and an aliphatic hydrocarbon group having a ring in the structure thereof.
The linear aliphatic hydrocarbon group has preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [—CH2—], an ethylene group [—(CH2)2-], a trimethylene group [—(CH2)3-], a tetramethylene group [—(CH2)4-], and a pentamethylene group [—(CH2)5-].
The branched aliphatic hydrocarbon group has preferably 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples thereof include alkylalkylene groups, for example, alkylmethylene groups such as —CH(CH3)—, —CH(CH2CH3)—, —C(CH3)2—, —C(CH3)(CH2CH3)—, —C(CH3)(CH2CH2CH3)—, and —C(CH2CH3)2—; alkylethylene groups such as —CH(CH3)CH2—, —CH(CH3)CH(CH3)—, —C(CH3)2CH2—, —CH(CH2CH3)CH2—, and —C(CH2CH3)2—CH2—; alkyltrimethylene groups such as —CH(CH3)CH2CH2— and —CH2CH(CH3)CH2—; and alkyltetramethylene groups such as —CH(CH3)CH2CH2CH2— and —CH2CH(CH3)CH2CH2—. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.
The above linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms which has been substituted with a fluorine atom, and a carbonyl group.
Examples of the aliphatic hydrocarbon group having a ring in the structure thereof include a cyclic aliphatic hydrocarbon group which may have a substituent having a heteroatom in the ring structure thereof (a group in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring), a group in which the cyclic aliphatic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, and a group in which the cyclic aliphatic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group. Examples of the linear or branched aliphatic hydrocarbon group include the same groups as described above.
The cyclic aliphatic hydrocarbon group has preferably 3 to 20 carbon atoms and more preferably 3 to 12 carbon atoms.
The cyclic aliphatic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which two hydrogen atoms have been removed from a polycycloalkane is preferable. As the polycycloalkane, a group having 7 to 12 carbon atoms is preferable. Specific examples of the polycycloalkane include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.
The cyclic aliphatic hydrocarbon group may or may not have a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, and a carbonyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and most preferably a methoxy group or an ethoxy group.
Examples of the halogen atom for the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is preferable.
Examples of the halogenated alkyl group as the substituent include groups in which some or all hydrogen atoms in the above-described alkyl groups have been substituted with the above-described halogen atoms.
In the cyclic aliphatic hydrocarbon group, some carbon atoms constituting the ring structure thereof may be substituted with a substituent having a heteroatom. As the substituent having a heteroatom, —O—, —C(═O)—O—, —S—, —S(═O)2—, or —S(═O)2—O— is preferable.
The aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
The aromatic ring is not particularly limited as long as the aromatic ring is a cyclic conjugated system having (4n+2) π electrons and may be monocyclic or polycyclic. The aromatic ring has preferably 5 to 30 carbon atoms, more preferably 5 to 20 carbon atoms, still more preferably 6 to 15 carbon atoms, and particularly preferably 6 to 12 carbon atoms. Here, the number of carbon atoms in a substituent is not included in the number of carbon atoms. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocyclic rings in which some carbon atoms constituting the above-described aromatic hydrocarbon rings have been substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocyclic ring include a pyridine ring and a thiophene ring.
Specific examples of the aromatic hydrocarbon group include a group (an arylene group or a heteroarylene group) obtained by removing two hydrogen atoms from the above-described aromatic hydrocarbon ring or the above-described aromatic heterocyclic ring; a group obtained by removing two hydrogen atoms from an aromatic compound (for example, biphenyl or fluorene) having two or more aromatic rings; and a group (for example, a group obtained by further removing one hydrogen atom from an aryl group in the arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group) obtained by substituting one hydrogen atom of a group (an aryl group or a heteroaryl group) obtained by removing one hydrogen atom from the above aromatic hydrocarbon ring or the above aromatic heterocyclic ring, with an alkylene group. The above-described alkylene group bonded to the aryl group or heteroaryl group has preferably 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and particularly preferably 1 carbon atom.
In the aromatic hydrocarbon group, the hydrogen atom in the aromatic hydrocarbon group may be substituted with a substituent. For example, the hydrogen atom bonded to the aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of substituents include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the alkoxy group, the halogen atom, and the halogenated alkyl group as the substituents include those described as the substituent that substitutes a hydrogen atom in the cyclic aliphatic hydrocarbon group.
Among these, Ra050 represents preferably an aliphatic hydrocarbon group having a ring in the structure, more preferably a cyclic aliphatic hydrocarbon group which may have a substituent having a heteroatom in the ring structure, and still more preferably an alicyclic hydrocarbon group which may have a substituent, which is a polycyclic group or a monocyclic group.
In Formula (a5-1), La0 represents a divalent linking group.
Examples of the divalent linking group as La0 include a non-hydrocarbon oxygen atom-containing linking group such as an oxygen atom (ether bond: —O—), an ester bond (—C(═O)—O—), an oxycarbonyl group (—O—C(═O)—), an amide bond (—C(═O)—NH—), a carbonyl group (—C(═O)—), or a carbonate bond (—O—C(═O)—O—); and combinations of the above-described non-hydrocarbon oxygen atom-containing linking groups with an alkylene group. Further, a sulfonyl group (—SO2—) may be further linked to the combination.
Examples of such a divalent linking group include linking groups each represented by General Formulae (L-a1-1) to (L-a1-8). Further, in General Formulae (L-a1-1) to (L-a1-8), V′101 in General Formulae (L-a1-1) to (L-a1-8) is bonded to Ra050 in Formula (a5-1).
[In the formulae, V′101 represents a single bond or an alkylene group having 1 to 5 carbon atoms, and V′102 represents a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.]
As the divalent saturated hydrocarbon group as V′102, an alkylene group having 1 to 30 carbon atoms is preferable, an alkylene group having 1 to 10 carbon atoms is more preferable, and an alkylene group having 1 to 5 carbon atoms is still more preferable.
The alkylene group as V′101 and V′102 may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferable.
Specific examples of the alkylene group as V′101 and V′102 include a methylene group [—CH2—]; an alkylmethylene group such as —CH(CH3)—, —CH(CH2CH3)—, —C(CH3)2—, —C(CH3)(CH2CH3)—, —C(CH3)(CH2CH2CH3)—, or —C(CH2CH3)2—; an ethylene group [—CH2CH2—]; an alkylethylene group such as —CH(CH3)CH2—, —CH(CH3)CH(CH3)—, —C(CH3)2CH2—, or —CH(CH)CH3)CH2—; a trimethylene group (n-propylene group) [—CH2CH2CH2—]; an alkyltrimethylene group such as —CH(CH3)CH2CH2— or —CH2CH(CH3)CH2—; a tetramethylene group [—CH2CH2CH2CH2—]; an alkyltetramethylene group such as —CH(CH3)CH2CH2CH2— or —CH2CH(CH3)CH2CH2—; and a pentamethylene group [—CH2CH2CH2CH2CH2—].
Further, a part of methylene group in the alkylene group as V′101 and V′102 may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. As the aliphatic cyclic group, a divalent group in which one hydrogen atom has been further removed from the cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group) as Ra′3 in Formula (a1-r-1) is preferable, and a cyclohexylene group, a 1,5-adamantylene group, or a 2,6-adamantylene group is more preferable.
La0 represents preferably a divalent linking group having an ester bond or a divalent linking group having an ether bond, more preferably a linking group represented by any of Formulae (L-a1-1) to (L-a1-5) and (L-a1-8), and still more preferably a linking group represented by Formula (L-a1-3) or (L-a1-8).
In Formula (a5-1), Ya0 represents a divalent linking group which may have a heteroatom or a single bond.
The divalent linking group as Ya0 is not particularly limited, and suitable examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom.
The divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom as Ya0 each have the same definition as that for the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, which are described as groups other than the polymerizable group as W01 described above.
Among the examples, Ya0 represents preferably a linear or branched alkylene group or a single bond and more preferably a single bond.
In Formula (a5-1), Ra051 and Ra052 each independently represent a hydrogen atom, a fluorine atom, or a fluorinated alkyl group.
The fluorinated alkyl groups as Ra051 and Ra052 are each preferably a linear or branched fluorinated alkyl group having 1 to 5 carbon atoms and more preferably a trifluoromethyl group.
In Formula (a5-1), it is preferable that at least one of Ra051 and Ra052 bonded to the carbon atom adjacent to SO3− is a fluorine atom from the viewpoint of acid strength.
In Formula (a5-1), no represents an integer of 1 to 4 and preferably 1, 2, or 3.
In Formula (a5-1), M′m+ represents an m-valent onium cation. Among these, it is preferable that M′m+ represents a sulfonium cation or an iodonium cation. m represents an integer of 1 or greater.
Preferred examples of the cation moiety ((M′m+)1/m) include organic cations each represented by General Formulae (ca-1) to (ca-3).
[In the formula, R201 to R207 each independently represent an aryl group which may have a substituent, an alkyl group which may have a substituent, or an alkenyl group which may have a substituent. R201 to R203, and R206 and R207 may be bonded to each other to form a ring with the sulfur atoms in the formulae. R208 and R209 each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R210 represents an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a —SO2-containing cyclic group which may have a substituent. L201 represents —C(═O)— or —C(═O)—O—.]
In General Formulae (ca-1) to (ca-3), examples of the aryl group as R201 to R207 include an unsubstituted aryl group having 6 to 20 carbon atoms. Among these, a phenyl group or a naphthyl group is preferable.
As the alkyl group as R201 to R207, a chain-like or cyclic alkyl group having 1 to 30 carbon atoms is preferable.
It is preferable that the alkenyl group as R201 to R207 has 2 to 10 carbon atoms.
Examples of the substituent that R201 to R207 and R210 may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an aryl group, and a group represented by any of General Formulae (ca-r-1) to (ca-r-8). Among these, from the viewpoint of enhancing the sensitivity, a halogen atom or a halogenated alkyl group is preferable, and a fluorine atom or a fluorinated alkyl group is more preferable.
[In the formulae, R′201's each independently represent a hydrogen atom, a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.]
Cyclic Group which May have Substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group indicates a hydrocarbon group that has no aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated. In general, it is preferable that the aliphatic hydrocarbon group is saturated.
The aromatic hydrocarbon group as R′201 is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group has preferably 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. Here, the number of carbon atoms in a substituent is not included in the number of carbon atoms.
Specific examples of the aromatic ring contained in the aromatic hydrocarbon group as R′201 include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or an aromatic heterocyclic ring in which some carbon atoms constituting any of these aromatic rings are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specific examples of the aromatic hydrocarbon group as R′201 include a group in which one hydrogen atom has been removed from the aromatic ring (an aryl group such as a phenyl group or a naphthyl group), and a group in which one hydrogen atom in the aromatic ring has been substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, I-naphthylethyl group, or a 2-naphthylethyl group). The alkylene group (alkyl chain in the arylalkyl group) has preferably 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and particularly preferably 1 carbon atom.
Examples of the cyclic aliphatic hydrocarbon group as R′201 include an aliphatic hydrocarbon group having a ring in the structure thereof.
Examples of the aliphatic hydrocarbon group having a ring in the structure thereof include an alicyclic hydrocarbon group (a group in which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), a group in which the alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, and a group in which the alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.
The alicyclic hydrocarbon group has preferably 3 to 20 carbon atoms and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane is preferable, and the number of carbon atoms of the polycycloalkane is preferably in a range of 7 to 30. Among these, a polycycloalkane having a crosslinked ring polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; and a polycycloalkane having a condensed ring polycyclic skeleton such as a cyclic group having a steroid skeleton are preferable as the polycycloalkane.
Among these examples, as the cyclic aliphatic hydrocarbon group as R′201, a group in which one or more hydrogen atoms have been removed from a monocycloalkane or a polycycloalkane is preferable, a group in which one hydrogen atom has been removed from a polycycloalkane is more preferable, an adamantyl group or a norbornyl group is particularly preferable, and an adamantyl group is most preferable.
The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group has preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms.
As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [—CH2—], an ethylene group [—(CH2)2—], a trimethylene group [—(CH2)3-], a tetramethylene group [—(CH2)4-], and a pentamethylene group [—(CH2)5-].
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples thereof include alkylalkylene groups, for example, alkylmethylene groups such as —CH(CH3)—, —CH(CH2CH3)—, —C(CH3)2—, —C(CH3)(CH2CH3)—, —C(CH3)(CH2CH2CH3)—, and —C(CH2CH3)2—; alkylethylene groups such as —CH(CH3)CH2—, —CH(CH3)CH(CH3)—, —C(CH3)2CH2—, —CH(CH2CH3)CH2—, and —C(CH2CH3)2—CH2—; alkyltrimethylene groups such as —CH(CH3)CH2CH2— and —CH2CH(CH3)CH2—; and alkyltetramethylene groups such as —CH(CH3)CH2CH2CH2— and —CH2CH(CH3)CH2CH2—. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.
Further, the cyclic hydrocarbon group as R′201 may have a heteroatom such as a heterocyclic ring. Specific examples thereof include lactone-containing cyclic groups each represented by General Formulae (a2-r-1) to (a2-r-7), —SO2-containing cyclic groups each represented by General Formulae (b5-r-1) to (b5-r-4), and other heterocyclic groups each represented by Chemical Formulae (r-hr-1) to (r-hr-16).
Examples of the substituent for the cyclic group as R′201 include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group is most preferable.
As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group is more preferable, and a methoxy group or an ethoxy group is most preferable.
As the halogen atom as a substituent, a fluorine atom is preferable.
Example of the above-described halogenated alkyl group as the substituent includes a group in which some or all hydrogen atoms in an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group are substituted with the above-described halogen atoms.
The carbonyl group as the substituent is a group that substitutes a methylene group (—CH2—) constituting the cyclic hydrocarbon group.
Chain-Like Alkyl Group which May have Substituent:
The chain-like alkyl group as R′201 may be linear or branched.
The linear alkyl group has preferably 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms.
The branched alkyl group has preferably 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples thereof include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.
Chain-Like Alkenyl Group which May have Substituent:
The chain-like alkenyl group as R′201 may be linear or branched, and the number of carbon atoms thereof is preferably in a range of 2 to 10, more preferably in a range of 2 to 5, still more preferably in a range of 2 to 4, and particularly preferably 3. Examples of the linear alkenyl group include a vinyl group, a propenyl group (an allyl group), and a butynyl group. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group.
Among the examples, as the chain-like alkenyl group, a linear alkenyl group is preferable, a vinyl group or a propenyl group is more preferable, and a vinyl group is particularly preferable.
Examples of the substituent for the chain-like alkyl group or alkenyl group as R′201 include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and a cyclic group as R′201.
Examples of the cyclic group which may have a substituent, the chain-like alkyl group which may have a substituent, and the chain-like alkenyl group which may have a substituent as R′201 include those for the acid dissociable group represented by Formula (a1-r-2) which are the exemplary examples of the cyclic group which may have a substituent and the chain-like alkyl group which may have a substituent, in addition to those described above.
Among the examples, R′201 represents preferably a cyclic group which may have a substituent and more preferably a cyclic hydrocarbon group which may have a substituent. More specific preferred examples thereof include a phenyl group, a naphthyl group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane, a lactone-containing cyclic group represented by any of General Formulae (a2-r-1) to (a2-r-7), and a —SO2-containing cyclic group represented by any of General Formulae (b5-1-1) to (b5-r-4).
In General Formulae (ca-1) to (ca-3), in a case where R201 to R203 and R206 and R207 are bonded to each other to form a ring with a sulfur atom in the formula, these groups may be bonded to each other via a heteroatom such as a sulfur atom, an oxygen atom, or a nitrogen atom, or a functional group such as a carbonyl group, —SO—, —SO2—, —SO3—, —COO—, —CONH— or —N(RN)— (RN represents an alkyl group having 1 to 5 carbon atoms). As a ring to be formed, a ring containing the sulfur atom in the formula in the ring skeleton thereof is preferably a 3- to 10-membered ring and particularly preferably a 5- to 7-membered ring containing the sulfur atom. Specific examples of the ring to be formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring.
R208 and R209 each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms and preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. In a case where R208 and R209 represent an alkyl group, R208 and R209 may be bonded to each other to form a ring.
R210 represents an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a —SO2— containing cyclic group which may have a substituent.
Examples of the aryl group as R210 include an unsubstituted aryl group having 6 to 20 carbon atoms. Among these, a phenyl group or a naphthyl group is preferable.
As the alkyl group as R210, a chain-like or cyclic alkyl group having 1 to 30 carbon atoms is preferable.
It is preferable that the alkenyl group as R210 has 2 to 10 carbon atoms.
The —SO2-containing cyclic group which may have a substituent as R210 is preferably “—SO2-containing polycyclic group” and more preferably a group represented by General Formula (b5-r-1).
Specific suitable examples of cations represented by Formula (ca-1) include cations each represented by Chemical Formulae (ca-1-1) to (ca-1-76).
From the viewpoint of enhancing the sensitivity, as the suitable cation represented by Formula (ca-1), a cation having a fluorine atom or a fluorinated alkyl group as a substituent is preferable, and a cation selected from the group consisting of cations each represented by Chemical Formulae (ca-1-69) to (ca-1-75) is particularly preferable.
[In the formulae, g1, g2, and g3 represent a repeating number, g1 represents an integer of 1 to 5, g2 represents an integer of 0 to 20, and g3 represents an integer of 0 to 20.]
[In the formulae. R″201 represents a hydrogen atom or a substituent, and examples of the substituent include the same groups as those for the substituents that R201 to R207 and R210 to R212 may have.]
Specific examples of suitable cations represented by Formula (ca-2) include a diphenyliodonium cation and a bis(4-tert-butylphenyl) iodonium cation.
Specific examples of suitable cations represented by Formula (ca-3) include cations each represented by Formulae (ca-3-1) to (ca-3-6).
Among the examples, an organic cation represented by General Formula (ca-1) is more preferable as the cation moiety ((M′m+)1/m).
Specific preferred examples of the constitutional unit (a5) are shown below.
In the formulae shown below, Rα represents a hydrogen atom, a methyl group, or a trifluoromethyl group. In the formulae, m and M′m+ each have the same definition as that for m and M′m+ in General Formula (a5-1).
The constitutional unit (a5) of the component (A1) may be used alone or two or more kinds thereof.
In a case where the component (A1) has the constitutional unit (a5), the proportion of the constitutional unit (a5) in the component (A1) is preferably in a range of 1% to 20% by mole, more preferably in a range of 2% to 15% by mole, and still more preferably in a range of 5% to 15% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the component (A1).
In a case where the proportion of the constitutional unit (a5) is greater than or equal to the lower limits of the above-described preferable ranges, the sensitivity is likely to be further increased. Meanwhile, in a case where the proportion thereof is less than or equal to the upper limits of the above-described preferable ranges, the constitutional unit (a10) and other constitutional units are likely to be balanced.
The component (A1) may further have a constitutional unit (a2) (here, constitutional units corresponding to the constitutional unit (a0) and the constitutional unit (a1) are excluded) containing a lactone-containing cyclic group, in addition to the constitutional unit (a0).
In a case where the component (A1) is used to form a resist film, the lactone-containing cyclic group of the constitutional unit (a2) is effective for increasing the adhesiveness of the resist film to the substrate. Further, in a case where the component (A1) contains the constitutional unit (a2), the lithography characteristics and the like are improved due to the effects of appropriately adjusting the acid diffusion length, increasing the adhesiveness of the resist film to the substrate, and appropriately adjusting the solubility during the development.
The term “lactone-containing cyclic group” indicates a cyclic group that has a ring (lactone ring) containing —O—C(═O)— in the ring skeleton. In a case where the lactone ring is counted as the first ring and the group contains only the lactone ring, the group is referred to as a monocyclic group. Further, in a case where the group has other ring structures, the group is referred to as a polycyclic group regardless of the structures. The lactone-containing cyclic group may be a monocyclic group or a polycyclic group.
The lactone-containing cyclic group in the constitutional unit (a2) is not particularly limited, and an optional constitutional unit can be used. Specific examples thereof include groups each represented by General Formulae (a2-r-1) to (a2-r-7).
[In the formulae, a plurality of Ra′21's each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, —COOR″, —OC(═O) R″, a hydroxyalkyl group, or a cyano group, R″ represents a hydrogen atom, an alkyl group, or a lactone-containing cyclic group, A″ represents an alkylene group having 1 to 5 carbon atoms which may have an oxygen atom (—O—) or a sulfur atom (—S—), an oxygen atom, or a sulfur atom, n′ represents an integer of 0 to 2, and m′ represents 0 or 1. * represents a bonding site.]
In General Formulae (a2-r-1) to (a2-r-7), it is preferable that the alkyl group as Ra′21 is an alkyl group having 1 to 6 carbon atoms. It is preferable that the alkyl group is linear or branched. Specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, and a hexyl group. Among these, a methyl group or ethyl group is preferable, and a methyl group is particularly preferable.
It is preferable that the alkoxy group as Ra′21 is an alkoxy group having 1 to 6 carbon atoms. Further, it is preferable that the alkoxy group is linear or branched. Specific examples of the alkoxy groups include a group formed by linking the above-described alkyl group exemplified as the alkyl group represented by Ra′21 to an oxygen atom (—O—).
As the halogen atom as Ra′21, a fluorine atom is preferable.
Examples of the halogenated alkyl group as Ra′21 include groups in which some or all hydrogen atoms in the alkyl group as Ra′21 are substituted with the halogen atoms. As the halogenated alkyl group, a fluorinated alkyl group is preferable, and a perfluoroalkyl group is particularly preferable.
In —COOR″ and —OC(═O)) R″ as Ra′21, each R″ represents a hydrogen atom, an alkyl group, or a lactone-containing cyclic group.
The alkyl group as R″ may be linear, branched, or cyclic and has preferably 1 to 15 carbon atoms.
In a case where R″ represents a linear or branched alkyl group, an alkyl group having 1 to 10 carbon atoms is preferable, an alkyl group having 1 to 5 carbon atoms is more preferable, and a methyl group or an ethyl group is particularly preferable.
In a case where R″ represents a cyclic alkyl group, the number of carbon atoms thereof is preferably in a range of 3 to 15, more preferably in a range of 4 to 12, and most preferably in a range of 5 to 10. Specific examples thereof include groups in which one or more hydrogen atoms have been removed from a monocycloalkane, which may or may not be substituted with a fluorine atom or a fluorinated alkyl group; and groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as bicycloalkane, tricycloalkane, or tetracycloalkane. More specific examples thereof include groups in which one or more hydrogen atoms have been removed from a monocycloalkane such as cyclopentane or cyclohexane; and groups in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane.
Examples of the lactone-containing cyclic group as R″ include the same groups as those for the groups each represented by General Formulae (a2-r-1) to (a2-r-7).
As the hydroxyalkyl group as Ra′21, a hydroxyalkyl group having 1 to 6 carbon atoms is preferable, and specific examples thereof include a group in which at least one hydrogen atom in the alkyl group as Ra′?′ has been substituted with a hydroxyl group.
Among the examples, it is preferable that Ra′21's each independently represent a hydrogen atom or a cyano group.
In General Formulae (a2-r-2), (a2-r-3) and (a2-r-5), as the alkylene group having 1 to 5 carbon atoms as A″, a linear or branched alkylene group is preferable, and examples thereof include a methylene group, an ethylene group, an n-propylene group, and an isopropylene group. In a case where the alkylene group has an oxygen atom or a sulfur atom, specific examples thereof include groups in which —O— or —S— is interposed in the terminal of the alkylene group or between the carbon atoms of the alkylene group. Further, examples thereof include —O—CH2—, —CH2—O—CH2—, —S—CH2—, and —CH2—S—CH2—. A″ represents preferably an alkylene group having 1 to 5 carbon atoms or —O—, more preferably an alkylene group having 1 to 5 carbon atoms, and most preferably a methylene group.
Specific examples of the groups each represented by General Formulae (a2-1-1) to (a2-r-7) are shown below.
As the constitutional unit (a2), a constitutional unit derived from acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α-position may be substituted with a substituent is preferable.
It is preferable that such a constitutional unit (a2) is a constitutional unit represented by General Formula (a2-1).
[In the formula, R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Ya21 represents a single bond or a divalent linking group. La21 represents —O—, —COO—, —CON(R′)—, —OCO—, —CONHCO—, or —CONHCS—, and R′ represents a hydrogen atom or a methyl group. Here, in a case where La21 represents-O—, Ya21 does not represent —CO—. Ra21 represents a lactone-containing cyclic group.]
In Formula (a2-1), R has the same definition as described above. R represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms and particularly preferably a hydrogen atom or a methyl group from the viewpoint of the industrial availability.
In Formula (a2-1), the divalent linking group as Ya21 is not particularly limited, and suitable examples thereof include a divalent hydrocarbon group which may have a substituent and a divalent linking group having a heteroatom, each of which has the same definition as the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, described as groups other than the polymerizable group represented by W01.
Ya21 represents preferably a single bond, an ester bond [—C(═O)—O)—], an ether bond (—O—), a linear or branched alkylene group, or a combination thereof and particularly preferably a single bond.
In Formula (a2-1), it is preferable that Ya21 represents a single bond and La21 represents —COO— or —OCO—.
In Formula (a2-1), Ra21 represents a lactone-containing cyclic group.
Suitable examples of the lactone-containing cyclic group as Ra21 include groups each represented by General Formulae (a2-r-1) to (a2-r-7).
Among these, groups each represented by General Formula (a2-r-1) or (a2-r-2) are preferable. Specifically, groups each represented by Chemical Formulae (r-lc-1-1) to (r-lc-1-7) and (r-lc-2-1) to (r-lc-2-18) are preferable, and groups each represented by
Chemical Formulae (r-lc-1-1), (r-lc-2-1), and (r-lc-2-7) are more preferable.
The constitutional unit (a2) included in the component (A1) may be used alone or two or more kinds thereof.
In a case where the component (A1) has the constitutional unit (a2), the proportion of the constitutional unit (a2) is preferably greater than 0% by mole and 20% by mole or less with respect to the total amount (100% by mole) of all constitutional units constituting the component (A1).
In a case where the proportion of the constitutional unit (a2) is greater than or equal to the lower limits of the above-described preferable ranges, the effect obtained by allowing the component (A1) to have the constitutional unit (a2) can be sufficiently achieved. Meanwhile, in a case where the proportion thereof is less than or equal to the above-described upper limits of the above-described preferable ranges, the constitutional unit (a2) and other constitutional units can be balanced, and various lithography characteristics are enhanced.
The constitutional unit (a8) is a constitutional unit derived from a compound represented by General Formula (a8-1).
[In the formula, W2 represents a polymerizable group-containing group. Yax2 represents a single bond or an (nax2+1)-valent linking group. Yax2 and W2 may form a condensed ring. R1 represents a fluorinated alkyl group having 1 to 12 carbon atoms. R2 represents an organic group having 1 to 12 carbon atoms which may have a fluorine atom or a hydrogen atom. R2 and Yax2 may be bonded to each other to form a ring structure. nax2 represents an integer of 1 to 3.]
The description of the polymerizable group-containing group as W2 in Formula (a8-1) is the same as the description of the polymerizable group-containing group as W01 in General Formula (a0-1).
Suitable examples of the polymerizable group-containing group as W2 include a group represented by Chemical Formula: C(RX11)(RX12)═C(RX13)—Yax0.
In the chemical formula, RX11, RX12, and RX13 each represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Yax0 represents a single bond or a divalent linking group and has the same definition as that for the group represented by Chemical Formula: C(RX11)(RX12)═C(RX13)—Yax0-described in the section of W01 in General Formula (a0-1).
Specific examples of the constitutional unit (a8) are shown below.
In the following formulae, Rα represents a hydrogen atom, a methyl group, or a trifluoromethyl group.
The constitutional unit (a8) contained in the component (A1) may be used alone or two or more kinds thereof.
In a case where the component (A1) contains the constitutional unit (a8), the proportion of the constitutional unit (a8) is preferably greater than 0% by mole and 20% by mole or less with respect to the total amount (100% by mole) of all constitutional units constituting the component (A1).
The component (A1) contained in the resist composition may be used alone or in combination of two or more kinds thereof.
In the resist composition according to the present embodiment, the component (A1) includes a polymer compound having a repeating structure of the constitutional unit (a0).
Among the examples, suitable examples of the component (A1) include a polymer compound having a repeating structure of the constitutional unit (a0) and the constitutional unit (a10).
More specific suitable examples of the polymer compound contained in the component (A1) include a polymer compound having a repeating structure of the constitutional unit (a0) and the constitutional unit (a10); a polymer compound having a repeating structure of the constitutional unit (a0), the constitutional unit (a10), and the constitutional unit (a5); and a polymer compound having a repeating structure of the constitutional unit (a0), the constitutional unit (a10), and the constitutional unit (a2).
In the polymer compound having a repeating structure of the constitutional unit (a0) and the constitutional unit (a10), the proportion of the constitutional unit (a0) is preferably in a range of 10% to 90% by mole, more preferably in a range of 20% to 80% by mole, still more preferably in a range of 30% to 70% by mole, and particularly preferably in a range of 40% to 65% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
In addition, the proportion of the constitutional unit (a10) in the polymer compound described above is preferably in a range of 10% to 90% by mole, more preferably in a range of 20% to 80% by mole, still more preferably in a range of 30% to 70% by mole, and particularly preferably in a range of 35% to 60% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
The proportion of the constitutional unit (a0) in the polymer compound having a repeating structure of the constitutional unit (a0), the constitutional unit (a10), and the constitutional unit (a5) is preferably in a range of 20% to 80% by mole, more preferably in a range of 30% to 70% by mole, and still more preferably in a range of 40% to 60% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
Further, the proportion of the constitutional unit (a10) in the polymer compound is preferably in a range of 5% to 60% by mole, more preferably in a range of 10% to 50% by mole, and still more preferably in a range of 20% to 40% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
In addition, the proportion of the constitutional unit (a5) in the polymer compound is preferably greater than 0% by mole and 20% by mole or less, more preferably in a range of 5% to 20% by mole, and still more preferably in a range of 5% to 15% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
The proportion of the constitutional unit (a0) in the polymer compound having a repeating structure of the constitutional unit (a0), the constitutional unit (a10), and the constitutional unit (a2) is preferably in a range of 20% to 80% by mole, more preferably in a range of 30% to 70% by mole, and still more preferably in a range of 40% to 60% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
Further, the proportion of the constitutional unit (a10) in the polymer compound is preferably in a range of 5% to 60% by mole, more preferably in a range of 10% to 50% by mole, and still more preferably in a range of 20% to 40% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
In addition, the proportion of the constitutional unit (a2) in the polymer compound is preferably greater than 0% by mole and 20% by mole or less, more preferably in a range of 5% to 20% by mole, and still more preferably in a range of 5% to 15% by mole with respect to the total amount (100% by mole) of all constitutional units constituting the polymer compound.
Such a component (A1) can be produced by dissolving a monomer, from which each constitutional unit is derived, in a polymerization solvent and adding a radical polymerization initiator such as azobisisobutylonitrile (AIBN) or dimethyl azobisisobutyrate (for example, V-601) to the solution so that the polymerization is carried out.
Alternatively, the component (A1) can be produced by dissolving, in a polymerization solvent, a monomer from which the constitutional unit (a0) is derived and, as necessary, a monomer from which a constitutional unit (for example, the constitutional unit (a10)) other than the constitutional unit (a0) is derived, adding a radical polymerization initiator as described above thereto to carry out polymerization, and carrying out a deprotection reaction.
Further, a —C(CF3)2—OH group may be introduced to the terminal during the polymerization using a combination of chain transfer agents such as HS—CH2—CH2—CH2—C(CF3)2—OH. As described above, a copolymer into which a hydroxyalkyl group, formed by substitution of some hydrogen atoms in the alkyl group with fluorine atoms, has been introduced is effective for reducing development defects and reducing line edge roughness (LER: uneven irregularities of a line side wall).
The weight-average molecular weight (Mw) (in terms of polystyrene according to gel permeation chromatography (GPC)) of the component (A1) is not particularly limited, but is preferably in a range of 1000 to 50000, more preferably in a range of 2000 to 30000, and still more preferably in a range of 3000 to 25000.
In a case where the Mw of the component (A1) is less than or equal to the upper limits of the above-described preferable ranges, the resist composition exhibits a satisfactory solubility in a resist solvent for a resist enough to be used as a resist. On the contrary, in a case where the Mw of the component (A1) is greater than or equal to the lower limits of the above-described preferable ranges, the dry etching resistance and the cross-sectional shape of the resist pattern is excellent.
The polydispersity (Mw/Mn) of the component (A1) is not particularly limited; however, it is preferably in a range of 1.0 to 3.0, more preferably in a range of 1.0 to 2.5, and particularly preferably in a range of 1.0 to 2.0. Further, Mn represents the number average molecular weight.
In the resist composition of the present embodiment, a base material component (hereinafter, also referred to as “component (A2)”) which does not correspond to the component (A1) and whose solubility in a developing solution is changed by the action of an acid may be used in combination as the component (A).
The component (A2) is not particularly limited and may be optionally selected from a plurality of components of the related art which have been known as base material components for a chemically amplified resist composition and used.
As the component (A2), a polymer compound or a low-molecular-weight compound may be used alone or in combination of two or more kinds thereof.
The proportion of the component (A1) in the component (A) is preferably 25% by mass or greater, more preferably 50% by mass or greater, and still more preferably 75% by mass or greater, and may be 100% by mass with respect to the total mass of the component (A). In a case where the proportion thereof is 25% by mass or greater, a resist pattern having excellent various lithography characteristics such as high sensitivity, high resolution, and the property of suppressing film reduction, and improved roughness is likely to be formed.
In the resist composition of the present embodiment, the content of the component (A) may be adjusted according to the thickness of the resist film intended to be formed.
The resist composition according to the present embodiment may further contain other components in addition to the component (A) described above. Examples of the other components include a component (B), a component (D), a component (E), a component (F), and a component(S), which are described below.
It is preferable that the resist composition according to the present embodiment further contains an acid generation agent component (B) that generates an acid upon light exposure.
The component (B) is not particularly limited, and those which have been suggested so far as an acid generation agent for a chemically amplified resist composition in the related art can be used.
Examples of the acid generation agent include various acid generation agents, for example, onium salt-based acid generation agents such as iodonium salts and sulfonium salts; oxime sulfonate-based acid generation agents; diazomethane-based acid generation agents such as bisalkyl or bisaryl sulfonyl diazomethanes and poly(bis-sulfonyl)diazomethanes; nitrobenzyl sulfonate-based acid generation agents, iminosulfonate-based acid generation agents, and disulfone-based acid generation agents.
Examples of the onium salt-based acid generation agents include a compound represented by General Formula (b-1) (hereinafter, also referred to as “component (b-1)”), a compound represented by General Formula (b-2) (hereinafter, also referred to as “component (b-2)”), and a compound represented by General Formula (b-3) (hereinafter, also referred to as “component (b-3)”).
[In the formulae, R101 and R104 to R108 each independently represent a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. R104 and R105 may be bonded to each other to form a ring structure. R102 represents a fluorinated alkyl group having 1 to 5 carbon atoms or a fluorine atom. Y101 represents a divalent linking group having an oxygen atom or a single bond. V101 to V103 each independently represent a single bond, an alkylene group, or a fluorinated alkylene group. L101 and L102 each independently represent a single bond or an oxygen atom. L103 to L105 each independently represent a single bond, —CO—, or —SO2—. m represents an integer of 1 or greater, and M″m+ represents an m-valent onium cation.]
Anions in Component (b-1)
In Formula (b-1), R101 represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent.
Cyclic Group which May have Substituent:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or an aliphatic hydrocarbon group. The aliphatic hydrocarbon group indicates a hydrocarbon group that has no aromaticity. Further, the aliphatic hydrocarbon group may be saturated or unsaturated. In general, it is preferable that the aliphatic hydrocarbon group is saturated.
The aromatic hydrocarbon group as R101 is a hydrocarbon group having an aromatic ring. The aromatic hydrocarbon group has preferably 3 to 30 carbon atoms, more preferably 5 to 30 carbon atoms, still more preferably 5 to 20 carbon atoms, particularly preferably 6 to 15 carbon atoms, and most preferably 6 to 10 carbon atoms. Here, the number of carbon atoms in a substituent is not included in the number of carbon atoms.
Specific examples of the aromatic ring of the aromatic hydrocarbon group as R101 include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, and an aromatic heterocyclic ring in which some carbon atoms constituting any of these aromatic rings are substituted with heteroatoms. Examples of the heteroatom in the aromatic heterocyclic rings include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specific examples of the aromatic hydrocarbon group as R101 include a group in which one hydrogen atom has been removed from the aromatic ring (an aryl group such as a phenyl group or a naphthyl group) and a group in which one hydrogen atom in the aromatic ring has been substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, 1-naphthylethyl group, or a 2-naphthylethyl group). The alkylene group (alkyl chain in the arylalkyl group) has preferably 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and particularly preferably 1 carbon atom.
Examples of the cyclic aliphatic hydrocarbon group as R101 include an aliphatic hydrocarbon group having a ring in the structure thereof.
Examples of the aliphatic hydrocarbon group having a ring in the structure thereof include an alicyclic hydrocarbon group (a group in which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), a group in which the alicyclic hydrocarbon group is bonded to the terminal of a linear or branched aliphatic hydrocarbon group, and a group in which the alicyclic hydrocarbon group is interposed in the middle of a linear or branched aliphatic hydrocarbon group.
The alicyclic hydrocarbon group has preferably 3 to 20 carbon atoms and more preferably 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. As the monocyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a monocycloalkane is preferable. The monocycloalkane has preferably 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. As the polycyclic alicyclic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane is preferable, and the number of carbon atoms of the polycycloalkane is preferably in a range of 7 to 30. Among these, a polycycloalkane having a crosslinked ring polycyclic skeleton such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; and a polycycloalkane having a condensed ring polycyclic skeleton such as a cyclic group having a steroid skeleton are preferable as the polycycloalkane.
Among these examples, as the cyclic aliphatic hydrocarbon group as R101, a group in which one or more hydrogen atoms have been removed from a monocycloalkane or a polycycloalkane is preferable, a group in which one hydrogen atom has been removed from a polycycloalkane is more preferable, an adamantyl group or a norbornyl group is still more preferable, and an adamantyl group is particularly preferable.
The linear aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group has preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, still more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [—CH2—], an ethylene group [—(CH2)2—], a trimethylene group [—(CH2)3—], a tetramethylene group [—(CH2)4-], and a pentamethylene group [—(CH2)3—].
The branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group has preferably 2 to 10 carbon atoms, more preferably 3 to 6 carbon atoms, still more preferably 3 or 4 carbon atoms, and most preferably 3 carbon atoms.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples thereof include alkylalkylene groups, for example, alkylmethylene groups such as —CH(CH3)—, —CH(CH2CH3)—, —C(CH3)2—, —C(CH3)(CH2CH3)—, —C(CH3)(CH2CH2CH3)—, and —C(CH2CH3)2—; alkylethylene groups such as —CH(CH3)CH2—, —CH(CH3)CH(CH3)—, —C(CH3)2CH2—, —CH(CH2CH3)CH2—, and —C(CH2CH3)2—CH2—; alkyltrimethylene groups such as —CH(CH3)CH2CH2— and —CH2CH(CH3)CH2—; and alkyltetramethylene groups such as —CH(CH3)CH2CH2CH2— and —CH2CH(CH3)CH2CH2—. As the alkyl group in the alkylalkylene group, a linear alkyl group having 1 to 5 carbon atoms is preferable.
Further, the cyclic hydrocarbon group as R101 may have a heteroatom such as a heterocyclic ring. Specific examples thereof include lactone-containing cyclic groups each represented by General Formulae (a2-r-1) to (a2-r-7), heterocyclic groups each represented by Chemical Formulae (r-hr-1) to (r-hr-16), and —SO2-containing cyclic groups each represented by General Formulae (b5-r-1) to (b5-r-4).
In the formulae, * represents a bonding site with respect to Y101 in Formula (b-1).
[In the formulae, Rb′51's each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, —COOR″, —OC(═O)R″, a hydroxyalkyl group, or a cyano group, R″ represents a hydrogen atom, an alkyl group, a lactone-containing cyclic group, or a-SO2-containing cyclic group, B″ represents an alkylene group having 1 to 5 carbon atoms which may have an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom, and n′ represents an integer of 0 to 2. * represents a bonding site.]
In General Formulae (b5-r-1) and (b5-r-2), B″ represents an alkylene group having 1 to 5 carbon atoms which may have an oxygen atom or a sulfur atom, an oxygen atom, or a sulfur atom.
B″ represents preferably an alkylene group having 1 to 5 carbon atoms or —O—, more preferably an alkylene group having 1 to 5 carbon atoms, and still more preferably a methylene group.
In General Formulae (b5-r-1) to (b5-r-4), Rb′51's each independently represent a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, —COOR″, —OC(═O) R″, a hydroxyalkyl group, or a cyano group.
Among these, it is preferable that Rb′51's each independently represent a hydrogen atom or a cyano group.
Specific examples of the groups each represented by General Formulae (b5-r-1) to (b5-r-1) are shown below. In the formulae shown below, “Ac” represents an acetyl group.
Examples of the substituent for the cyclic group as R101 include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, and a nitro group.
As the alkyl group as the substituent, an alkyl group having 1 to 5 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group is most preferable.
As the alkoxy group as the substituent, an alkoxy group having 1 to 5 carbon atoms is preferable, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group is more preferable, and a methoxy group or an ethoxy group is most preferable.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among these, a bromine atom and an iodine atom are preferable, and an iodine atom is more preferable.
Example of the above-described halogenated alkyl group as the substituent includes a group in which some or all hydrogen atoms in an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group have been substituted with the above-described halogen atoms.
The carbonyl group as the substituent is a group that substitutes a methylene group (—CH2—) constituting the cyclic hydrocarbon group.
The cyclic hydrocarbon group as R101 may be a condensed cyclic group having a condensed ring in which an aliphatic hydrocarbon ring and an aromatic ring are condensed. Examples of the condensed ring include those obtained by condensing one or more aromatic rings with a polycycloalkane having a crosslinked ring polycyclic skeleton. Specific examples of the crosslinked ring polycycloalkane include a bicycloalkane such as bicyclo[2.2.1]heptane (norbornane) and bicyclo[2.2.2]octane. As the condensed cyclic group, a group having a condensed ring in which two or three aromatic rings are condensed with a bicycloalkane is preferable, and a group having a condensed ring in which two or three aromatic rings are condensed with bicyclo[2.2.2]octane is more preferable. Specific suitable examples of the condensed cyclic group as R101 include groups represented by Formulae (r-br-1) and (r-br-2).
In the formulae, * represents a bonding site with respect to Y101 in Formula (b-1).
Examples of the substituent that the condensed cyclic group as R101 may have include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an aromatic hydrocarbon group, and an alicyclic hydrocarbon group.
Examples of the alkyl group, the alkoxy group, the halogen atom, and the halogenated alkyl group as the substituent of the condensed cyclic group include those described as the substituent of the cyclic group as R101.
Examples of the aromatic hydrocarbon group as the substituent of the condensed cyclic group include a group in which one hydrogen atom has been removed from the aromatic ring (an aryl group such as a phenyl group or a naphthyl group), a group in which one hydrogen atom in the aromatic ring has been substituted with an alkylene group (for example, an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, 1-naphthylethyl group, or a 2-naphthylethyl group), and a heterocyclic group represented by any of Chemical Formulae (r-hr-1) to (r-hr-6).
Examples of the alicyclic hydrocarbon group as the substituent of the condensed cyclic group include a group in which one hydrogen atom has been removed from a monocycloalkane such as cyclopentane or cyclohexane, a group in which one hydrogen atom has been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane, a lactone-containing cyclic group represented by any of General Formulae (a2-r-1) to (a2-r-7), a —SO2-containing cyclic group represented by any of General Formulae (b5-r-1) to (b5-r-4), and a heterocyclic group represented by any of Chemical Formulae (r-hr-7) to (r-hr-16).
Chain-Like Alkyl Group which May have Substituent:
The chain-like alkyl group as R101 may be linear or branched.
The linear alkyl group has preferably 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms.
The branched alkyl group has preferably 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples thereof include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.
Chain-Like Alkenyl Group which May have Substituent:
The chain-like alkenyl group as R101 may be linear or branched, and the number of carbon atoms thereof is preferably in a range of 2 to 10, more preferably in a range of 2 to 5, still more preferably in a range of 2 to 4, and particularly preferably 3. Examples of the linear alkenyl group include a vinyl group, a propenyl group (an allyl group), and a butynyl group. Examples of the branched alkenyl group include a 1-methylvinyl group, a 2-methylvinyl group, a 1-methylpropenyl group, and a 2-methylpropenyl group.
Among the examples, as the chain-like alkenyl group, a linear alkenyl group is preferable, a vinyl group or a propenyl group is more preferable, and a vinyl group is particularly preferable.
Examples of the substituent for the chain-like alkyl group or alkenyl group as R101 include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, and a cyclic group as R101.
Among the examples, R101 represents preferably a cyclic group which may have a substituent and more preferably a cyclic hydrocarbon group which may have a substituent.
More specifically, as the cyclic hydrocarbon group, an aromatic hydrocarbon group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane, a lactone-containing cyclic group represented by any of General Formulae (a2-r-1) to (a2-r-7), a —SO2-containing cyclic group represented by any of General Formulae (b5-r-1) to (b5-r-4), and a condensed cyclic group having a condensed ring in which an aliphatic hydrocarbon ring and an aromatic ring are condensed are preferable, and an aromatic hydrocarbon group and a condensed cyclic group having a condensed ring in which an aliphatic hydrocarbon ring and an aromatic ring are condensed are more preferable.
Among these, it is still more preferable that R101 represents an alkyl group having 1 to 5 carbon atoms, an aryl group having a substituent selected from the group consisting of a bromine atom and an iodine atom, or a group represented by any of Formulae (r-br-1) and (r-br-2).
In Formula (b-1), Y101 represents a divalent linking group having an oxygen atom or a single bond.
In a case where Y101 represents a divalent linking group containing an oxygen atom, Y101 may contain an atom other than the oxygen atom. Examples of atoms other than an oxygen atom include a carbon atom, a hydrogen atom, a sulfur atom, and a nitrogen atom.
Examples of the divalent linking group having an oxygen atom include a non-hydrocarbon oxygen atom-containing linking group such as an oxygen atom (an ether bond: —O—), an ester bond (—C(═O)—O—), an oxycarbonyl group (—O—C(═O)—), an amide bond (—C(═O)—NH—), a carbonyl group (—C(═O)—), or a carbonate bond (—O—C(═O)—O—); and combinations of the above-described non-hydrocarbon oxygen atom-containing linking groups with an alkylene group. Further, a sulfonyl group (—SO2—) may be further linked to the combination. Examples of the divalent linking group having an oxygen atom include linking groups each represented by General Formulae (y-a1-1) to (y-a1-7).
Further, in General Formulae (y-a1-1) to (y-a1-7), V′101 in General Formulae (y-a1-1) to (y-a1-7) is bonded to R101 in Formula (b-1).
[In the formulae, V′100 represents an alkylene group having 1 to 5 carbon atoms or a single bond, and V′102 represents a divalent saturated hydrocarbon group having 1 to 30 carbon atoms or a single bond.]
As the divalent saturated hydrocarbon group as V′102, an alkylene group having 1 to 30 carbon atoms is preferable, an alkylene group having 1 to 10 carbon atoms is more preferable, and an alkylene group having 1 to 5 carbon atoms is still more preferable.
The alkylene group as V′101 and V′102 may be a linear alkylene group or a branched alkylene group, and a linear alkylene group is preferable.
Specific examples of the alkylene group as V′101 and V′102 include a methylene group [—CH2—]; an alkylmethylene group such as —CH(CH3)—, —CH(CH2CH3)—, —C(CH3)2—, —C(CH3)(CH2CH3)—, —C(CH3)(CH)CH2CH3)—, or —C(CH2CH3)2—; an ethylene group [—CH2CH2—]; an alkylethylene group such as —CH(CH3)CH2—, —CH(CH3)CH(CH3)—, —C(CH3)2CH2, or —CH(CH2CH3)CH2; a trimethylene group (n-propylene group) [—CH2CH2CH2—]; an alkyltrimethylene group such as —CH(CH3)CH2CH2— or —CH2CH(CH3)CH2—; a tetramethylene group [—CH2CH2CH2CH2—]; an alkyltetramethylene group such as —CH(CH3)CH2CH2CH2— or —CH2CH(CH3)CH2CH2—; and a pentamethylene group [—CH2CH2CH2CH2CH2—].
Further, a part of methylene group in the alkylene group as V′101 and V′102 may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. As the aliphatic cyclic group, a divalent group in which one hydrogen atom has been further removed from the cyclic aliphatic hydrocarbon group (a monocyclic aliphatic hydrocarbon group or a polycyclic aliphatic hydrocarbon group) as Ra′3 in Formula (a1-r-1) is preferable, and a cyclohexylene group, a 1,5-adamantylene group, or a 2,6-adamantylene group is more preferable.
Y101 represents preferably a divalent linking group having an ester bond or a divalent linking group having an ether bond and more preferably an ester bond (—C(═O)—O—), an oxycarbonyl group (—O—C(═O)—), or a linking group represented by any of Formulae (y-a1-1) to (y-a1-5).
In Formula (b-1), viol represents a single bond, an alkylene group, or a fluorinated alkylene group. It is preferable that the alkylene group and the fluorinated alkylene group as V″101 have 1 to 4 carbon atoms. Examples of the fluorinated alkylene group as V101 include a group in which some or all hydrogen atoms in the alkylene group as V101 have been substituted with fluorine atoms. Among these examples, it is preferable that V101 represents a single bond or a fluorinated alkylene group having 1 to 4 carbon atoms.
In Formula (b-1), R102 represents a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. R102 represents preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms and more preferably a fluorine atom.
In a case where Y101 represents a single bond, specific example of the anion moiety represented by Formula (b-1) include a fluorinated alkylsulfonate anion such as a trifluoromethanesulfonate anion or a perfluorobutanesulfonate anion. Further, in a case where Y101 represents a divalent linking group having an oxygen atom, specific examples thereof include an anion represented by any of Formulae (an-1) to (an-3).
[In the formulae, R″101 represents an aliphatic cyclic group which may have a substituent, a —SO2-containing cyclic group represented by any of General Formulae (b5-r-1) to (b5-r-4), a monovalent heterocyclic group represented by any of Chemical Formulae (r-hr-1) to (r-hr-6), an aryl group which may have a substituent, a condensed cyclic group represented by Chemical Formula (r-br-1) or (r-br-2), or a chain-like alkyl group which may have a substituent. R″102 represents an aliphatic cyclic group which may have a substituent, a condensed cyclic group represented by Formula (r-br-1) or (r-br-2), a lactone-containing cyclic group represented by any of General Formulae (a2-r-1) and (a2-r-3) to (a2-r-7), or a —SO2-containing cyclic group represented by any of General Formulae (b5-r-1) to (b5-1-4). R″103 represents an aromatic cyclic group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain-like alkenyl group which may have a substituent. V″101 represents a single bond, an alkylene group having 1 to 4 carbon atoms, or a fluorinated alkylene group having 1 to 4 carbon atoms. R102 represents a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. Each v″ independently represents an integer of 0 to 3, each q″ independently represents an integer of 0 to 20, and n″ represents 0 or 1.]
As the aliphatic cyclic group as R″101, R″102, and R″103 which may have a substituent, the same groups as those for the cyclic aliphatic hydrocarbon group as R101 in Formula (b-1) are preferable. Examples of the substituent include the same groups as those for the substituent which may substitute the cyclic aliphatic hydrocarbon group as R101 in Formula (b-1).
As the aryl group which may have a substituent as R″101, an alkyl group having 1 to 5 carbon atoms or an aryl group having a substituent selected from the group consisting of a bromine atom and an iodine atom is preferable, from the viewpoint of enhancing the sensitivity, an aryl group having a substituent selected from the group consisting of a bromine atom and an iodine atom is more preferable, and an aryl group having an iodine atom as a substituent is still more preferable.
As the aromatic cyclic group as R″103 which may have a substituent, the same groups as those for the aromatic hydrocarbon group in the cyclic hydrocarbon group as R101 in Formula (b-1) are preferable. Examples of the substituent include the same groups as those for the substituent which may substitute the aromatic hydrocarbon group as R101 in Formula (b-1).
As the chain-like alkyl group as R″101 which may have a substituent, the same groups as those for the chain-like alkyl group as R101 in Formula (b-1) are preferable.
As the chain-like alkenyl group as R″103 which may have a substituent, the same groups as those for the chain-like alkenyl group as R101 in Formula (b-1) are preferable.
Anions in Component (b-2)
In Formula (b-2), R104 and R105 each independently represent a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, each of which has the same definition as that for R101 in Formula (b-1). Here. R104 and R105 may be bonded to each other to form a ring.
R104 and R105 represent preferably a chain-like alkyl group which may have a substituent and more preferably a linear or branched alkyl group or a linear or branched fluorinated alkyl group.
The chain-like alkyl group has preferably 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, and still more preferably 1 to 3 carbon atoms. It is preferable that the number of carbon atoms in the chain-like alkyl group as R104 and R105 decreases within the range of the number of carbon atoms from the viewpoints of the satisfactory solubility in a solvent for a resist and the like.
In the chain-like alkyl group as R104 and R105, it is preferable that the number of hydrogen atoms substituted with fluorine atoms is as large as possible from the viewpoint that the acid strength increases and the transparency to high energy light or electron beams having a wavelength of 250 nm or less is improved. The proportion of fluorine atoms in the chain-like alkyl group, that is, the fluorination ratio is preferably in a range of 70% to 100% and more preferably in a range of 90% to 100%, and it is most preferable that the chain-like alkyl group is a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms.
In Formula (b-2), V102 and V103 each independently represent a single bond, an alkylene group, or a fluorinated alkylene group, and examples thereof include the same groups as those for V101 in Formula (b-1).
In Formula (b-2), L101 and L102 each independently represent a single bond or an oxygen atom.
Anions in Component (b-3)
In Formula (b-3), R106 to R108 each independently represent a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and examples thereof include the same groups as those for R101 in Formula (b-1).
In Formula (b-3), L103 to L105 each independently represent a single bond, —CO—, or —SO2—.
Among the examples, as the anion moiety of the component (B), an anion in the component (b-1) is preferable.
In Formulae (b-1), (b-2), and (b-3), M′m+ represents an m-valent onium cation.
Among these, it is preferable that M′m+ represents a sulfonium cation or an iodonium cation. m represents an integer of 1 or greater.
Preferred examples of the cation moiety ((M′m+)1/m) include organic cations each represented by General Formulae (ca-1) to (ca-3).
Specific suitable examples of cations represented by Formula (ca-1) include cations each represented by Chemical Formulae (ca-1-1) to (ca-1-76).
From the viewpoint of enhancing the sensitivity, as the suitable cation represented by Formula (ca-1), a cation having a fluorine atom or a fluorinated alkyl group as a substituent is preferable, and a cation selected from the group consisting of cations each represented by Chemical Formulae (ca-1-69) to (ca-1-75) is particularly preferable.
Specific examples of suitable cations represented by Formula (ca-2) include a diphenyliodonium cation and a bis(4-tert-butylphenyl) iodonium cation.
Specific examples of the suitable cations each represented by Formula (ca-3) include cations each represented by Formulae (ca-3-1) and (ca-3-6) shown below.
Among the examples, an organic cation represented by General Formula (ca-1) is more preferable as the cation moiety ((M′m+)1/m).
Specific suitable examples of the component (B) in the resist composition according to the present embodiment are shown below.
In the resist composition according to the present embodiment, it is preferable to use, as the component (B), at least one selected from the group consisting of compounds each represented by Chemical Formulae (B-1) to (B-11). Among these, from the viewpoints of enhancing the sensitivity and the resolution, it is more preferable to use at least one selected from the group consisting of compounds each represented by Chemical Formulae (B-1) to (B-3).
In the resist composition according to the present embodiment, the component (B) may be used alone or in combination of two or more kinds thereof.
In a case where the resist composition contains the component (B), the content of the component (B) in the resist composition is preferably less than 60 parts by mass, more preferably in a range of 8 to 50 parts by mass, and still more preferably in a range of 20 to 50 parts by mass with respect to 100 parts by mass of the component (A1).
In a case where the content of the component (B) is set to be in the above-described preferable ranges, pattern formation can be sufficiently carried out. Further, it is preferable that each component of the resist composition is dissolved in an organic solvent from the viewpoint that a uniform solution is easily obtained and the storage stability of the resist composition is improved.
It is preferable that the resist composition according to the present embodiment further contains a base component (hereinafter, also referred to as “component (D)”) that traps (that is, controls the acid diffusion) an acid that is generated upon light exposure, in addition to the component (A1) or the component (A1) and the component (B). Such a component (D) acts as a quencher (an acid diffusion control agent) that traps acid that is generated in the resist composition upon exposure.
Examples of the component (D) include a photodecomposable base (D1) having an acid diffusion controllability (hereinafter, referred to as “component (D1)”) which is lost by the decomposition upon light exposure and a nitrogen-containing organic compound (D2) (hereinafter, referred to as “component (D2)”) which does not correspond to the component (D1). Among these, the photodecomposable base (the component (D1)) is preferable since it is easy to enhance the roughness reducing property. Further, in a case where the component (D1) is contained, both the characteristics of enhancing the sensitivity and suppressing the occurrence of coating defects are likely to be enhanced.
In a case where a resist composition containing the component (D1) is obtained, the contrast between an exposed portion and an unexposed portion of the resist film can be further improved in a case of forming a resist pattern.
The component (D1) is not particularly limited as long as the component is decomposed upon light exposure and loses an acid diffusion controllability, and one or more compounds selected from the group consisting of a compound represented by General Formula (d1-1) (hereinafter, referred to as “component (d1-1)”), a compound represented by General Formula (d1-2) (hereinafter, referred to as “component (d1-2)”), and a compound represented by General Formula (d1-3) (hereinafter, referred to as “component (d1-3)”) are preferable.
Since the components (d1-1) to (d1-3) are decomposed and lose the acid diffusion controllability (basicity), the components (d1-1) to (d1-3) do not function as a quencher at the exposed portion of the resist film, but function as a quencher at the unexposed portion of the resist film.
[In the formulae, Rd1 to Rd4 represent a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent. Here, no fluorine atom is bonded to the carbon atom adjacent to the S atom in Rd2 of Formula (d1-2). Yd1 represents a divalent linking group or a single bond. m represents an integer of 1 or greater, and Mm+'s each independently represent an m-valent organic cation.]
{Component (d1-1)}
In Formula (d1-1), Rd′ represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and examples thereof include the same groups as those for R′201.
Among these, Rd1 represents preferably an aromatic hydrocarbon group which may have a substituent, an aliphatic cyclic group which may have a substituent, or a chain-like alkyl group which may have a substituent and more preferably an aromatic hydrocarbon group which may have a substituent.
Examples of the substituent that these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a fluorine atom, a bromine atom, an iodine atom, a fluorinated alkyl group, lactone-containing cyclic groups each represented by General Formulae (a2-r-1) to (a2-r-7), an ether bond, an ester bond, and a combination thereof.
In a case where an ether bond or an ester bond is included as the substituent, the substituent may be bonded through an alkylene group, and a linking group represented by any of Formulae (y-a1-1) to (y-a1-5) is preferable as the substituent. Further, in a case where the aromatic hydrocarbon group, the aliphatic cyclic group, or the chain-like alkyl group as Rd1 contain a linking group represented by any of General Formulae (y-a1-1) to (y-a1-7) as a substituent, V′101 in General Formulae (y-a1-1) to (y-a1-7) is bonded to the carbon atom constituting the aromatic hydrocarbon group, the aliphatic cyclic group, or the chain-like alkyl group as Rd1 in Formula (d1-1), in General Formulae (y-a1-1) to (y-a1-7).
Suitable examples of the aromatic hydrocarbon group include a phenyl group, a naphthyl group, and a polycyclic structure having a bicyclooctane skeleton (for example, a polycyclic structure formed of a bicyclooctane skeleton and a ring structure other than the bicyclooctane skeleton).
As the aliphatic cyclic group, a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane is more preferable.
It is preferable that the chain-like alkyl group has 1 to 10 carbon atoms, and specific examples thereof include a linear alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, or a decyl group; and a branched alkyl group such as a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, or a 4-methylpentyl group.
In a case where the chain-like alkyl group is a fluorinated alkyl group having a fluorine atom or a fluorinated alkyl group as a substituent, the fluorinated alkyl group has preferably 1 to 11 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 4 carbon atoms. The fluorinated alkyl group may have an atom other than a fluorine atom. Examples of the atom other than a fluorine atom include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specific preferred examples of the anion moiety in the component (d1-1) are described below.
In Formula (d1-1). Mm+ represents an m-valent organic cation.
Suitable examples of the organic cation as Mat include those for the cations each represented by General Formulae (ca-1) to (ca-3). Among these, a cation represented by General Formula (ca-1) is more preferable, and a cation represented by any of Chemical Formulae (ca-1-1) to (ca-1-76) is still more preferable. From the viewpoint of enhancing the sensitivity, a cation having a fluorine atom or a fluorinated alkyl group as a substituent is preferable, and a cation selected from the group consisting of cations each represented by Chemical Formulae (ca-1-69) to (ca-1-75) is particularly preferable.
The component (d1-1) may be used alone or in combination of two or more kinds thereof.
{Component (d1-2)}
In Formula (d1-2), Rd2 represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and examples thereof include the same groups as those for R′201.
Here, no fluorine atom is bonded to the carbon atom adjacent to the S atom in Rd2 (the carbon atom is not substituted with fluorine). In this manner, the anion of the component (d1-2) is an appropriately weak acid anion, thereby improving the quenching ability of the component (D).
Rd2 represents preferably a chain-like alkyl group which may have a substituent or an aliphatic cyclic group which may have a substituent and more preferably an aliphatic cyclic group which may have a substituent.
The chain-like alkyl group preferably has 1 to 10 carbon atoms and more preferably 3 to 10 carbon atoms.
The aliphatic cyclic group is more preferably a group (which may have a substituent) obtained by removing one or more hydrogen atoms from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like; and a group obtained by removing one or more hydrogen atoms from camphor.
The hydrocarbon group as Rd2 may have a substituent, and examples of the substituent include the same groups as those for the substituent that the hydrocarbon group (such as an aromatic hydrocarbon group, an aliphatic cyclic group, or a chain-like alkyl group) as Rd1 in Formula (d1-1) may have.
Specific preferred examples of the anion moiety in the component (d1-2) are described below.
In Formula (d1-2), Mm+ represents an m-valent organic cation and has the same definition as that for Mm+ in Formula (d1-1).
The component (d1-2) may be used alone or in combination of two or more kinds thereof.
{Component (d1-3)}
In Formula (d1-3), Rd3 represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and examples thereof include the same groups as those for R′201. Among these, a cyclic group having a fluorine atom, a chain-like alkyl group, or a chain-like alkenyl group is preferable. Among these, a fluorinated alkyl group is preferable, and the same groups as those for the fluorinated alkyl group represented by Rd1 are more preferable.
In Formula (d1-3), Rd4 represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent, or a chain-like alkenyl group which may have a substituent, and examples thereof include the same groups as those for R′201.
Among these, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, an alkenyl group which may have a substituent, or a cyclic group which may have a substituent is preferable.
It is preferable that the alkyl group as Rd4 is a linear or branched alkyl group having 1 to 5 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. Some hydrogen atoms in the alkyl group as Rd4 may be substituted with a hydroxyl group, a cyano group, or the like.
It is preferable that the alkoxy group as Rd4 is an alkoxy group having 1 to 5 carbon atoms, and specific examples of the alkoxy group having 1 to 5 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, and a tert-butoxy group. Among these, a methoxy group and an ethoxy group are preferable.
Examples of the alkenyl group as Rd4 include the same groups as those for the alkenyl group as R′201. Among these, a vinyl group, a propenyl group (an allyl group), a 1-methylpropenyl group, and a 2-methylpropenyl group are preferable. These groups may have an alkyl group having 1 to 5 carbon atoms or a halogenated alkyl group having 1 to 5 carbon atoms as a substituent.
Examples of the cyclic group as Rd4 include the same groups as those for the cyclic group as R′201. Among these, an alicyclic group in which one or more hydrogen atoms have been removed from a cycloalkane such as cyclopentane, cyclohexane, adamantane, norbornane, isobornane, tricyclodecane or tetracyclododecane or an aromatic group such as a phenyl group or a naphthyl group is preferable. In a case where Rd4 represents an alicyclic group, the resist composition is satisfactorily dissolved in an organic solvent so that the lithography characteristics are enhanced. Further, in a case where Rd4 represents an aromatic group, the resist composition has excellent light absorption efficiency in lithography using EUV or the like as an exposure light source, and thus the sensitivity and lithography characteristics are enhanced.
In Formula (d1-3), Yd1 represents a single bond or a divalent linking group.
The divalent linking group as Yd1 is not particularly limited, and examples thereof include a divalent hydrocarbon group (an aliphatic hydrocarbon group or an aromatic hydrocarbon group) which may have a substituent and a divalent linking group having a heteroatom. The divalent hydrocarbon group and the divalent linking group each have the same definition as that for the divalent hydrocarbon group which may have a substituent and the divalent linking group having a heteroatom, described as groups other than the polymerizable group represented by W01.
It is preferable that Yd1 represents a carbonyl group, an ester bond, an amide bond, an alkylene group, or a combination thereof. As the alkylene group, a linear or branched alkylene group is more preferable, and a methylene group or an ethylene group is still more preferable.
Specific preferred examples of the anion moiety in the component (d1-3) are described below.
In Formula (d1-3), Mm+ represents an m-valent organic cation and has the same definition as that for Mm+ in Formula (d1-1).
The component (d1-3) may be used alone or in combination of two or more kinds thereof.
As the component (D1), only one of the above-described components (d1-1) to (d1-3) or a combination of two or more kinds thereof may be used.
In a case where the resist composition contains the component (D1), the content of the component (D1) in the resist composition is preferably in a range of 0.5 to 25 parts by mass, more preferably in a range of 1 to 20 parts by mass, and still more preferably in a range of 3 to 15 parts by mass with respect to 100 parts by mass of the component (A1).
In a case where the content of the component (D1) is greater than or equal to the lower limits of the above-described preferable ranges, particularly satisfactory lithography characteristics and a particularly satisfactory resist pattern shape are likely to be obtained. Meanwhile, in a case where the content thereof is less than or equal to the upper limits of the above-described preferable ranges, the sensitivity can be satisfactorily maintained, and the throughput is also excellent.
In the resist composition according to the present embodiment, it is preferable that the component (D1) contains the component (d1-1).
The content of the component (d1-1) in the entire component (D) contained in the resist composition according to the present embodiment is preferably 50% by mass or greater, more preferably 70% by mass or greater, and still more preferably 90% by mass or greater, and the component (D) may consist of only the component (d1-1) (100% by mass).
The methods of producing the component (d1-1) and the component (d1-2) are not particularly limited, and these components can be produced by known methods.
Further, the method of producing the component (d1-3) is not particularly limited, and the component is produced by the same method as disclosed in United States Patent Application, Publication No. 2012-0149916.
The component (D) may contain a nitrogen-containing organic compound component (hereinafter, referred to as “component (D2)”) that does not correspond to the component (D1) described above.
The component (D2) is not particularly limited as long as the component functions as an acid diffusion control agent and does not correspond to the component (D1), and an optional component may be selected from known components and then used. Among the examples, an aliphatic amine is preferable, and particularly a secondary aliphatic amine and a tertiary aliphatic amine are more preferable.
The aliphatic amine is an amine containing one or more aliphatic groups, and the number of carbon atoms in the aliphatic group is preferably in a range of 1 to 12.
Examples of the aliphatic amine include amines in which at least one hydrogen atom of ammonia NH; has been substituted with an alkyl group or hydroxyalkyl group having 12 or less carbon atoms (alkylamines or alkylalcoholamines), and cyclic amines.
Specific examples of the alkylamines and the alkylalcoholamines include monoalkylamines such as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, and n-decylamine; dialkylamines such as diethylamine, di-n-propylamine, di-n-heptylamine, di-n-octylamine, and dicyclohexylamine; trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine, tri-n-decylamine, and tri-n-dodecylamine; and alkylalcoholamines such as diethanolamine, triethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Among these, a trialkylamine having 6 to 30 carbon atoms is still more preferable, and tri-n-pentylamine or tri-n-octylamine is particularly preferable.
Examples of the cyclic amine include a heterocyclic compound having a nitrogen atom as a heteroatom. The heterocyclic compound may be a monocyclic compound (aliphatic monocyclic amine) or a polycyclic compound (aliphatic polycyclic amine).
Specific examples of the aliphatic monocyclic amine include piperidine and piperazine.
The aliphatic polycyclic amine preferably has 6 to 10 carbon atoms, and specific examples thereof include 1, 5-diazabicyclo[4.3.0]-5-nonene, 1,8-diazabicyclo[5.4.0]-7-undecene, hexamethylenetetramine, and 1,4-diazabicyclo[2.2.2]octane.
Examples of other aliphatic amines include tris(2-methoxymethoxyethyl)amine, tris{2-(2-methoxyethoxy)ethyl}amine, tris{2-(2-methoxyethoxymethoxy)ethyl}amine, tris {2-(1-methoxyethoxy)ethyl}amine, tris {2-(1-ethoxyethoxy)ethyl}amine, tris{2-(1-ethoxypropoxy)ethyl}amine, tris[2-{2-(2-hydroxyethoxy) ethoxy}ethyl]amine and triethanol amine triacetate, and triethanol amine triacetate is preferable.
As the component (12), an aromatic amine may be used.
Examples of the aromatic amine include 4-dimethylaminopyridine, 2,6-di-tert-butylpyridine, pyrrole, indole, pyrazole, imidazole, and derivatives thereof, tribenzylamine, 2,6-diisopropylaniline, and N-tert-butoxycarbonylpyrrolidine.
Among the examples, the component (D2) is preferably an alkylamine and more preferably a trialkylamine having 6 to 30 carbon atoms.
The component (D2) may be used alone or in combination of two or more kinds thereof.
In a case where the resist composition contains the component (D2), the content of the component (D2) in the resist composition is preferably in a range of 0.01 to 5 parts by mass, more preferably in a range of 0.1 to 5 parts by mass, and still more preferably in a range of 0.5 to 5 parts by mass with respect to 100 parts by mass of the component (A1).
In a case where the content of the component (D2) is greater than or equal to the lower limits of the above-described preferable ranges, particularly satisfactory lithography characteristics and a particularly satisfactory resist pattern shape are likely to be obtained. Meanwhile, in a case where the content thereof is less than or equal to the upper limits of the above-described preferable ranges, the sensitivity can be satisfactorily maintained, and the throughput is also excellent.
<<At Least One Compound (E) Selected from Group Consisting of Organic Carboxylic Acids, Phosphorus Oxo Acids, and Derivatives Thereof>>
For the purpose of preventing any deterioration in sensitivity and improving the resist pattern shape and the post-exposure temporal stability, the resist composition according to the present embodiment may contain, as an optional component, at least one compound (E) (hereinafter referred to as “component (E)”) selected from the group consisting of an organic carboxylic acid, and a phosphorus oxo acid and a derivative thereof.
Specific examples of the organic carboxylic acid include acetic acid, malonic acid, citric acid, malic acid, succinic acid, benzoic acid, and salicylic acid. Among these, salicylic acid is preferable.
Examples of the phosphorus oxo acid include phosphoric acid, phosphonic acid, and phosphinic acid. Among these, phosphonic acid is particularly preferable.
In the resist composition of the present embodiment, the component (E) may be used alone or in combination of two or more kinds thereof.
In a case where the resist composition contains the component (E), the content of the component (E) is preferably in a range of 0.01 to 5 parts by mass and more preferably in a range of 0.05 to 3 parts by mass with respect to 100 parts by mass of the component (A1). In a case where the content thereof is in the above-described ranges, the lithography characteristics are further improved.
The resist composition according to the present embodiment may contain a fluorine additive component (hereinafter, referred to as “component (F)”) as a hydrophobic resin. The component (F) is used to impart water repellency to the resist film, where it is used as a resin different from the component (A) to improve lithography characteristics.
As the component (F), for example, the fluorine-containing polymer compounds described in Japanese Unexamined Patent Application, First Publication Nos. 2010-002870, 2010-032994, 2010-277043, 2011-13569, and 2011-128226 can be used.
Specific examples of the component (F) include a polymer having a constitutional unit (f1) represented by General Formula (f1-1). As the polymer, a polymer (homopolymer) formed of only the constitutional unit (f1) represented by Formula (f1-1); a copolymer of the constitutional unit (f1) and the constitutional unit (a1); or a copolymer of the constitutional unit (f1), a constitutional unit derived from acrylic acid or methacrylic acid, and the constitutional unit (a1) is preferable, and a copolymer of the constitutional unit (f1) and the constitutional unit (a1) is more preferable. Here, as the constitutional unit (a1) copolymerized with the constitutional unit (f1), a constitutional unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate or a constitutional unit derived from 1-methyl-1-adamantyl (meth)acrylate is preferable, and a constitutional unit derived from 1-ethyl-1-cyclooctyl (meth)acrylate is more preferable.
[In the formula, R has the same definition as described above, Rf102 and Rf103 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Rf102 and Rf103 may be the same as or different from each other. nf1 represents an integer of 0 to 5, and Rf101 represents an organic group having a fluorine atom.]
In Formula (f1-1), R bonded to the carbon atom at the α-position has the same definition as described above. It is preferable that R represents a hydrogen atom or a methyl group.
In Formula (f1-1), a fluorine atom is preferable as the halogen atom as Rf102 and Rf103. Examples of the alkyl group having 1 to 5 carbon atoms as Rf102 and Rf103 include the same groups as those for the alkyl group having 1 to 5 carbon atoms as R. Among the examples, a methyl group or an ethyl group is preferable. Specific examples of the halogenated alkyl group having 1 to 5 carbon atoms as Rf102 and Rf103 include groups in which some or all hydrogen atoms of an alkyl group having 1 to 5 carbon atoms are substituted with halogen atoms. Among these, a fluorine atom is preferable as the halogen atom. Among these, Rf102 and Rf103 represent preferably a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 5 carbon atoms, more preferably a hydrogen atom, a fluorine atom, a methyl group, or an ethyl group, and still more preferably a hydrogen atom.
In Formula (f1-1), nf1 represents an integer of 0 to 5, preferably an integer of 0 to 3, and more preferably 1 or 2.
In Formula (f1-1). Rf10 represents an organic group having a fluorine atom and preferably a hydrocarbon group having a fluorine atom.
The hydrocarbon group having a fluorine atom may be linear, branched, or cyclic, and the number of carbon atoms thereof is preferably in a range of 1 to 20, more preferably in a range of 1 to 15, and still more preferably in a range of 1 to 10.
In the hydrocarbon group having a fluorine atom, preferably 25% or more of the hydrogen atoms in the hydrocarbon group are fluorinated, more preferably 50% or more thereof are fluorinated, and particularly preferably 60% or more thereof are fluorinated from the viewpoint of increasing the hydrophobicity of the resist film during immersion exposure.
Among the examples, Rf101 represents more preferably a fluorinated hydrocarbon group having 1 to 6 carbon atoms and particularly preferably a trifluoromethyl group, —CH2—CF3, —CH2—CF2—CF3, —CH(CF3)2, —CH2—CH2—CF3, or —CH2—CH2—CF2—CF2—CF2—CF3.
The weight-average molecular weight (Mw) (in terms of polystyrene according to gel permeation chromatography) of the component (F) is preferably in a range of 1000 to 50000, more preferably in a range of 5000 to 40000, and most preferably in a range of 10000 to 30000. In a case where the weight-average molecular weight thereof is less than or equal to the upper limits of the above-described ranges, the resist composition exhibits a satisfactory solubility in a solvent for a resist enough to be used as a resist. Meanwhile, in a case where the weight-average molecular weight thereof is greater than or equal to the lower limits of the above-described ranges, water repellency of the resist film is improved.
Further, the polydispersity (Mw/Mn) of the component (F) is preferably in a range of 1.0 to 5.0, more preferably in a range of 1.0 to 3.0, and most preferably in a range of 1.0 to 2.5.
In the resist composition according to the present embodiment, the component (F) may be used alone or in combination of two or more kinds thereof.
In a case where the resist composition contains the component (F), the content of the component (F) is preferably in a range of 0.5 to 10 parts by mass and more preferably in a range of 1 to 10 parts by mass with respect to 100 parts by mass of the component (A1).
The resist composition of the present embodiment can be produced by dissolving the resist materials in an organic solvent component (hereinafter, referred to as “component(S)”).
The component(S) may be any organic solvent which can dissolve each component to be used to obtain a uniform solution, and an optional organic solvent can be appropriately selected from those which have been known as solvents of a chemically amplified resist composition and then used.
Examples of the component(S) include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; compounds having an ester bond, such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, and dipropylene glycol monoacetate; polyhydric alcohol derivatives of compounds having an ether bond such as monoalkyl ether or monophenyl ether, such as monomethylether, monoethylether, monopropylether, or monobutylether of polyhydric alcohols or compounds having an ester bond [among these, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferable]; cyclic ethers such as dioxane; esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethylbenzylether, cresylmethylether, diphenylether, dibenzylether, phenetole, butylphenylether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, and mesitylene; and dimethylsulfoxide (DMSO).
In the resist composition of the present embodiment, the component(S) may be used alone or in the form of a mixed solvent of two or more kinds thereof. Among these, PGMEA, PGME, y-butyrolactone, EL, or cyclohexanone is preferable.
Further, a mixed solvent obtained by mixing PGMEA with a polar solvent is also preferable as the component(S). The blending ratio (mass ratio) of the mixed solvent can be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, but is preferably in the range of 1:9 to 9:1 and more preferably in a range of 2:8 to 8:2.
More specifically, in a case where EL or cyclohexanone is blended as the polar solvent, the mass ratio of PGMEA to EL or cyclohexanone is preferably in a range of 1:9 to 9:1 and more preferably in a range of 2:8 to 8:2. Further, in a case where PGME is blended as the polar solvent, the mass ratio of PGMEA to PGME is preferably in a range of 1:9 to 9:1, more preferably in a range of 2:8 to 8:2, and still more preferably in a range of 3:7 to 7:3. Further, a mixed solvent of PGMEA, PGME, and cyclohexanone is also preferable.
Further, a mixed solvent of y-butyrolactone and at least one selected from PGMEA and EL is also preferable as the component(S). In this case, as the mixing ratio, the mass ratio between the former and the latter is preferably in a range of 70:30 to 95:5.
The amount of the component(S) to be used is not particularly limited and is appropriately set to have a concentration which enables coating a substrate or the like depending on the thickness of the coated film. The component(S) is typically used in an amount such that the solid content concentration of the resist composition is set to be in a range of 0.1% to 20% by mass and preferably in a range of 0.2% to 15% by mass.
After the resist material is dissolved in the component(S), impurities may be removed from the resist composition of the present embodiment using a porous polyimide film, a porous polyamideimide film, or the like. For example, the resist composition may be filtered using a filter formed of a porous polyimide film, a filter formed of a porous polyamideimide film, a filter formed of a porous polyimide film and a porous polyamideimide film, or the like. Examples of the porous polyimide film and the porous polyamideimide film include those described in Japanese Unexamined Patent Application, First Publication No. 2016-155121.
As described above, the resist composition according to the present embodiment contains the resin component (A1) having the constitutional unit (a0) derived from a compound represented by General Formula (a0-1).
The constitutional unit (a0) contains an aromatic group (RAr) and a specific acid dissociable group (Ra0)) in a side chain thereof. Since the specific acid dissociable group (Ra0) has a plurality of carbon-carbon multiple bonds having a triple bond, a resonance effect is exhibited in the resin component (A1) during the acid dissociation reaction, and thus the acid dissociation properties are enhanced.
In addition, since the constitutional unit (a0) has the aromatic group (RAr) and a plurality of carbon-carbon multiple bonds, the carbon ratio is increased (the number of CH bonds is suppressed to be low) in the resin component (A1).
For these reasons, according to the resist composition of the present embodiment, which contains the resin component (A1) having the constitutional unit (a0), the etching resistance can be further enhanced, and the sensitivity can also be enhanced.
A method for forming a resist pattern according to the second aspect according to the present invention is a method including a step of forming a resist film on a support using the resist composition according to the first aspect of the present invention described above, a step of exposing the resist film to light, and a step of developing the resist film exposed to light to form a resist pattern.
According to the embodiment of the method for forming a resist pattern, a method for forming a resist pattern by performing processes as described below is an exemplary example.
First, a support is coated with the resist composition of the above-described embodiment using a spinner or the like, and a bake (post applied bake (PAB)) treatment is performed under a temperature condition of 80° C. to 150° C. for 40 to 120 seconds and preferably 60 to 90 seconds to form a resist film.
Next, the selective exposure is performed on the resist film by, for example, light exposure through a mask (mask pattern) having a predetermined pattern formed thereon using an exposure apparatus such as an electron beam lithography apparatus or an ArF exposure apparatus, or direct irradiation with an electron beam for drawing without using a mask pattern, and a bake treatment (post exposure bake (PEB)) is carried out, for example, under a temperature condition of 80° C. to 150° C. for 40 to 120 seconds and preferably 60 to 90 seconds.
Next, the resist film is subjected to a developing treatment. The developing treatment is conducted using an alkali developing solution in a case of an alkali developing process and using a developing solution containing an organic solvent (organic developing solution) in a case of a solvent developing process.
After the developing treatment, it is preferable to conduct a rinse treatment. As the rinse treatment, water rinsing using pure water is preferable in a case of the alkali developing process, and rinsing using a rinse solution containing an organic solvent is preferable in a case of the solvent developing process.
In a case of the solvent developing process, the developing solution or the rinse solution attached onto the pattern may be removed by a treatment using a supercritical fluid after the developing treatment or the rinse treatment.
After the developing treatment or the rinse treatment, drying is conducted. As desired, a bake treatment (post bake) may be conducted after the developing treatment.
In this manner, a resist pattern can be formed.
The support is not particularly limited and a known support of the related art can be used, and examples thereof include a substrate for an electronic component and a substrate on which a predetermined wiring pattern has been formed. Specific examples thereof include a metal substrate such as a silicon wafer, copper, chromium, iron, or aluminum; and a glass substrate. As the materials of the wiring pattern, copper, aluminum, nickel, or gold can be used.
The wavelength used for light exposure is not particularly limited and the exposure can be conducted using radiation such as an ArF excimer laser, a KrF excimer laser, an F2 excimer laser, extreme ultraviolet rays (EUV), vacuum ultraviolet rays (VUV), electron beans (EB), X-rays, and soft X-rays.
The resist composition according to the above-described embodiment is highly useful for a KrF excimer laser, an Ar excimer laser, BB, and EUV, more useful for an ArF excimer laser, EB, and EUV, and particularly useful for EB and EUV. That is, the method for forming a resist pattern according to the present embodiment is a method particularly useful in a case where the step of exposing the resist film to light includes a process of exposing the resist film to extreme ultraviolet (EUV) rays or electron beams (EB).
The method of exposing the resist film to light can be a general exposure (dry exposure) conducted in air or an inert gas such as nitrogen, or liquid immersion exposure (liquid immersion lithography).
The liquid immersion exposure is an exposure method in which the region between the resist film and the lens at the lowermost position of the exposure apparatus is filled with a solvent (liquid immersion medium) in advance that has a refractive index greater than the refractive index of air, and the exposure (immersion exposure) is conducted in this state.
The liquid immersion medium is preferably a solvent that exhibits a refractive index greater than the refractive index of air but less than the refractive index of the resist film to be exposed, and examples thereof include water, a fluorine-based inert liquid, a silicon-based solvent, and a hydrocarbon-based solvent. As the liquid immersion medium, water is suitably used.
As the alkali developing solution used for the developing treatment in the alkali developing process, a 0.1 to 10 mass % tetramethylammonium hydroxide (TMAH) aqueous solution is an exemplary example.
The content of the organic solvent in the organic developing solution used for the developing treatment in the solvent developing process is typically 90% by mass of greater, and may be 95% by mass or greater, 98% by mass or greater, 100% by mass, and preferably 100% by mass with respect to the total amount of the organic developing solution.
The organic solvent contained in the organic developing solution may be obtained by dissolving the component (A) (component (A) before exposure) and can be appropriately selected from known organic solvents. Specific examples thereof include a polar solvent such as a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, a nitrile-based solvent, an amide-based solvent, and an ether-based solvent, and a hydrocarbon-based solvent.
Examples of the ester-based solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butyl butanoate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, and butyl propionate.
Examples of the nitrile-based solvent include acetonitrile, propionitrile, valeronitrile, and butyronitrile.
Known additives can be blended into the organic developing solution as necessary. Examples of the additive include a surfactant. The surfactant is not particularly limited, and for example, an ionic or non-ionic fluorine-based and/or silicon-based surfactant can be used. As the surfactant, a non-ionic surfactant is preferable, and a non-ionic fluorine-based surfactant or a non-ionic silicon-based surfactant is more preferable.
In a case where a surfactant is blended into the solution, the amount of the surfactant to be blended is typically in a range of 0.001% to 5% by mass, preferably in a range of 0.005% to 2% by mass, and more preferably in a range of 0.01% to 0.5% by mass with respect to the total amount of the organic developing solution.
The developing treatment can be performed according to a known developing method, and examples thereof include a method for immersing a support in a developing solution for a certain time (a dip method), a method for raising a developing solution on the surface of a support using the surface tension and maintaining the state for a certain time (a puddle method), a method for spraying a developing solution to the surface of a support (spray method), and a method for continuously ejecting a developing solution onto a support rotating at a certain rate while scanning a developing solution ejection nozzle at a certain rate (dynamic dispense method).
As the organic solvent contained in the rinse solution used for the rinse treatment after the developing treatment in the solvent developing process, a solvent that is unlikely to dissolve a resist pattern can be appropriately selected from the organic solvents described as the organic solvent used in the organic developing solution and then used. Typically, at least one solvent selected from a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, an amide-based solvent, and an ether-based solvent is used. Among these, at least one solvent selected from a hydrocarbon-based solvent, a ketone-based solvent, an ester-based solvent, an alcohol-based solvent, and an amide-based solvent is preferable, at least one solvent selected from an alcohol-based solvent and an ester-based solvent is more preferable, and an alcohol-based solvent is particularly preferable.
As the alcohol-based solvent used in the rinse solution, a monohydric alcohol having 6 to 8 carbon atoms is preferable, and the monohydric alcohol may be linear, branched, or cyclic. Specific examples thereof include 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and benzyl alcohol. Among these, 1-hexanol, 2-heptanol, and 2-hexanol are preferable, and 1-hexanol and 2-hexanol are more preferable.
These organic solvents may be used alone or in combination of two or more kinds thereof. Further, an organic solvent other than the above-described solvents and water may be mixed and used. However, in consideration of the development characteristics, the amount of water to be blended into the rinse solution is preferably 30% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less, and particularly preferably 3% by mass or less with respect to the total amount of the rinse solution.
A known additive can be blended into the rinse solution as necessary. Examples of the additive include a surfactant. As the surfactant, the same surfactants as those described above are exemplary examples. Among these, a non-ionic surfactant is preferable, and a non-ionic fluorine-based surfactant or a non-ionic silicon-based surfactant is more preferable.
In a case where a surfactant is blended into the solution, the amount of the surfactant to be blended is typically in a range of 0.001% to 5% by mass, preferably in a range of 0.005% to 2% by mass, and more preferably in a range of 0.01% to 0.5% by mass with respect to the total amount of the rinse solution.
The rinse treatment carried out using a rinse solution (washing treatment) can be performed according to a known rinse method. Examples of the method for performing the rinse treatment include a method for continuously ejecting a rinse solution onto a support rotating at a certain rate (rotary coating method), a method for immersing a support in a rinse solution for a certain time (dip method), and a method for spraying a rinse solution to the surface of a support (spray method).
According to the method for forming a resist pattern of the present embodiment described above, since the above-described resist composition is used, a resist pattern in which the sensitivity is enhanced and the etching resistance is further enhanced can be formed.
It is preferable that various materials that are used in the resist composition according to the above-described embodiment and the pattern forming method according to the above-described embodiment (for example, a resist solvent, a developing solution, a rinse solution, a composition for forming an antireflection film, and a composition for forming a top coat) do not contain impurities such as a metal, a metal salt containing halogen, an acid, an alkali, and a component having a sulfur atom or phosphorus atom.
Here, examples of the impurities containing metal atoms include Na, K, Ca, Fe, Cu, Mn, Mg, Al, Cr, Ni, Zn, Ag, Sn, Pb, Li, and salts thereof. The content of the impurities contained in these materials is preferably 200 ppb or less, more preferably 1 ppb or less, still more preferably 100 parts per trillion (ppt) or less, particularly preferably 10 ppt or less, and most preferably substantially zero (less than or equal to the detection limit of the measuring device).
(Compound Represented by General Formula (a0-1))
The compound according to a third aspect of the present invention is a compound represented by General Formula (a0-1).
[In Formula (a0-1), W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
The compound represented by General Formula (a0)-1) is the same as the compound represented by General Formula (a0-1) in the resist composition according to the embodiment described above.
In Formula (a0-1), suitable examples of W01 include a group represented by Chemical Formula: C(RX11)(RX12)═C(RX13)—Yax0-. In the chemical formula, RX11, RX12, and RX13 each represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms, and Yax0 represents a single bond or a divalent linking group. RX11 and RX12 each represent preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, more preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom. In addition, RX13 represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, more preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom. Yax0 represents more preferably an ester bond [—C(═O)—O—or —O—C(═O)—] or a single bond and still more preferably a single bond.
In Formula (a0-1), RAT represents preferably a group in which two hydrogen atoms have been removed from benzene, naphthalene, anthracene, or biphenyl, which may have a substituent, more preferably a group in which two hydrogen atoms have been removed from benzene which may have a substituent or a group in which two hydrogen atoms have been removed from naphthalene which may have a substituent, and still more preferably a group in which two hydrogen atoms have been removed from benzene which may have a substituent.
Alternatively, from the viewpoint of enhancing the sensitivity, RAr represents preferably an aromatic group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and more preferably an aromatic group having a hydroxy group as a substituent. Among these, a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from benzene, naphthalene, anthracene, or biphenyl is more preferable, a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from benzene or a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from naphthalene is still more preferable, a group having a substituent selected from the group consisting of a hydroxy group and an alkoxy group and obtained by removing two hydrogen atoms from benzene is particularly preferable, and a group having a hydroxy group as a substituent and obtained by removing two hydrogen atoms from benzene is most preferable.
In Formula (a0-r-1), suitable examples of Ra01, Ra02, Ra03, and Ra04 include a case where Ra01 represents a linear hydrocarbon group and all of Ra02, Ra03, and Ra04 represent a hydrogen atom; a case where Ra03 and Ra04 are bonded to each other to form an aromatic ring structure; and a case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure.
Suitable examples of the case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure include a case where Ra01 and Ra02 are bonded to each other to form an alicyclic structure and Ra03 and Ra04 each represent a linear or branched alkyl group or a hydrogen atom; and a case where the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure formed by Ra03 and Ra04 being bonded to each other are condensed to form a condensed ring structure.
In Formula (a0-r-1), it is preferable that Ra05 represents a linear or branched saturated hydrocarbon group (alkyl group) or a hydrogen atom.
It is preferable that the compound according to the present embodiment is a compound represented by General Formula (a0-1-m0).
[In the formula, Rm represents an alkyl group having 1 to 5 carbon atoms, a halogenated alkyl group having 1 to 5 carbon atoms, a halogen atom, or a hydrogen atom. L1 represents a divalent linking group or a single bond. Ra06 represents a hydrogen atom or an alkyl group. m represents an integer of 0 to 3. n represents an integer of 0 or greater. Here, n≤4+2m is satisfied. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
In Formula (a0-1-m0), as the alkyl group having 1 to 5 carbon atoms as Rm, a linear or branched alkyl group having 1 to 5 carbon atoms is preferable, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group. The halogenated alkyl group having 1 to 5 carbon atoms is a group in which some or all hydrogen atoms in the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. As the halogen atom, a fluorine atom is particularly preferable.
Rm represents preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms and most preferably a hydrogen atom or a methyl group from the viewpoint of industrial availability.
In Formula (a0-1-m0), L1, Ra06, m, n, Ra0, Ra01, Ra02, Ra03, and Ra04 each have the same definition as that for as L1, Ra06, m, n, Ra0, Ra01, Ra02, Ra03, and Ra04 in General Formula (a0-1-u0).
Preferred specific examples of the compound according to the present embodiment are shown below.
In the formulae shown below, Rα represents a hydrogen atom, a methyl group, or a trifluoromethyl group.
[Method of Producing Compound (a0-1)]
The compound according to the present embodiment can be produced by, for example, a production method including a step (P) of reacting (esterifying) a compound represented by Formula (C0-1) with a compound represented by Formula (A1c-1) to obtain a compound (a0-1).
[In Formula (a0-1), W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
W01, RAr, Ra0, Ra01, Ra02, Ra03, Ra04, and Ra05 in the chemical formulae each have the same definition as described above.
The reaction temperature condition in the step (P) is not particularly limited, and is, for example, about 0° C. to 120° C.
The reaction time of the step (P) is not particularly limited, and is, for example, about 1 to 72 hours.
Examples of the reaction solvent used in the step (P) include dichloromethane, dichloroethane, chloroform, tetrahydrofuran, N,N-dimethylformamide, acetonitrile, propionitrile, N,N′-dimethylacetamide, and dimethyl sulfoxide.
In addition, a condensing agent and a basic catalyst may be used in the reaction of the step (P).
Specific examples of the condensing agent include N,N′-dicyclohexylcarbodiimide, N,N′-diisopropylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride, and carbonyldiimidazole (CDI).
Specific examples of the basic catalyst include tertiary amines such as trimethylamine, triethylamine, and tributylamine, aromatic amines such as pyridine, dimethylaminopyridine, and pyrrolidinopyridine, diazabicyclononene (DBN), and diazabicycloundecene (DBU).
In the method of producing the compound (a0-1) described above, the compound in the reaction solution may be isolated and purified after completion of each reaction. A known method in the related art can be used for isolation and purification, and for example, concentration, solvent extraction, distillation, crystallization, recrystallization, or chromatography can be appropriately combined and used.
The structure of the compound obtained as described above can be identified by typical organic analysis methods such as 1H-nuclear magnetic resonance (NMR) spectroscopy, 13C-NMR spectroscopy, 19F-NMR spectroscopy, infrared (IR) absorption spectroscopy, mass spectrometry (MS), an elemental analysis method, and an X-ray crystal diffraction method.
As the raw material that is used in each step, a commercially available raw material may be used, or a synthetic raw material may be used.
The compound according to the present embodiment described above is a monomer useful for producing a polymer compound according to a fourth aspect described below.
A polymer compound according to the fourth aspect of the present invention has a constitutional unit derived from a compound represented by General Formula (a0-1).
[In Formula (a0-1), W01 represents a polymerizable group-containing group. RAr represents an aromatic group which may have a substituent. Ra0 represents an acid dissociable group represented by General Formula (a0-r-1). Ra01 represents an aliphatic hydrocarbon group. Ra02, Ra03, and Ra04 each independently represent a hydrocarbon group which may have a substituent, or a hydrogen atom. Ra01 and Ra02 may be bonded to each other to form an alicyclic structure. Ra03 and Ra04 may be bonded to each other to form an aromatic ring structure or an alicyclic structure. Alternatively, the alicyclic structure formed by Ra01 and Ra02 being bonded to each other and the aromatic ring structure or alicyclic structure formed by Ra03 and Ra04 being bonded to each other may be condensed to each other. Ra05 represents a chain-like or alicyclic hydrocarbon group or a hydrogen atom. * represents a bonding site with respect to an oxy group (—O—) to which Ra0 is bonded.]
W01, RAr, Ra0, Ra01, Ra02, Ra03, Ra04, and Ra05 in Formula (a0-1) each have the same definition as described above.
Suitable examples of the polymer compound according to the fourth aspect of the present invention include a polymer compound having a repeating structure of the constitutional unit (a0) and the constitutional unit (a10) described above.
Such a polymer compound is useful as a base material component of the resist composition.
Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.
Each of a compound (a0-1-1) to a compound (a0-1-8) was produced by the synthesis method described below.
[Synthesis of Compound (a0-1-1)]
10.0 g of 4-vinylbenzoic acid was dissolved in 40 g of tetrahydrofuran, and the solution was added dropwise to a mixed solution of 12.8 g of diazabicycloundecene (DBU), 8.4 g of ethynyl methyl vinyl carbinol, 15.3 g of carbonyl diimidazole (CDI), and 40 g of tetrahydrofuran under ice-cooling. Thereafter, the mixture was stirred at 60° C. for 4 hours, the solvent was distilled off, 80 g of heptane was added to the residues, and mixture was filtered to remove impurities. Next, the resultant was purified by column chromatography, thereby obtaining a compound (a0-1-1).
The obtained compound (a0-1-1) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHZ): δ (ppm)=7.90 (d, —Ar—, 2H), 7.60 (d, —Ar—, 2H), 6.78-6.84 (m, —CH═, 1H), 5.95 (d, ═CH2, 1H), 5.89 (t, —CH═, 1H), 5.41 (d, ═CH2, 1H), 5.25-5.30 (m, ═CH2, 2H), 3.61 (s, ═CH, 1H), 1.64 (s, —CH3, 3H)
[Synthesis of Compounds (a0-1-2) to (a0-1-8)]
Each of a compound (a0-1-2) to a compound (a0-1-8) was obtained by the same synthesis method as in [Synthesis of compound (a0-1-1)] using the corresponding raw material alcohol.
The structures of the obtained compounds (a0-1-2) to (a0-1-8) and the data of the NMR measurement thereof are shown below.
The obtained compound (a0-1-2) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHz): δ (ppm)=7.88 (d, —Ar—, 2H), 7.59 (d, —Ar—, 2H), 7.28-7.33 (m, —Ar, 5H), 6.77-6.84 (m, —CH═, 1H), 5.94 (d, ═CH2, 1H), 5.42 (d, ═CH2, 1H), 3.59 (s, ═CH, 1H), 2.00 (s, —CH3, 3H)
The obtained compound (a0-1-3) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHz): δ (ppm)=7.92 (d, —Ar—, 2H), 7.60 (d, —Ar—, 2H), 6.79-6.86 (m, —CH═, 1H), 6.21 (d, —CH═CH—, 1H), 5.96 (d, ═CH2, 1H), 5.81 (d, —CH═CH—, 1H), 5.40 (d, ═CH2, 1H), 3.62 (s, ═CH, 1H), 2.23-2.58 (m, —CH2-CH2-, 4H)
The obtained compound (a0-1-4) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHz): δ (ppm)=7.90 (d, —Ar—, 2H), 7.58 (d, —Ar—, 2H), 6.77-6.84 (m, —CH═, 1H), 5.96 (d, ═CH2, 1H), 5.67-5.80 (m, —CH═CH—, 2H), 5.40 (d, ═CH2, 1H), 3.58 (s, ═CH, 1H), 1.60-2.33 (m, —(CH2) 3-, 6H)
The obtained compound (a0-1-5) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHz): δ (ppm)=10.75 (s, —OH, 1H), 6.95-7.75 (m, —Ar—, 3H), 6.65-6.74 (m, —CH═, 1H), 5.89 (t, —CH═, 1H), 5.72 (d, —CH2, 1H), 5.17 (d, ═CH2, 1H), 5.27-5.31 (m, ═CH2, 2H), 3.60 (s, ═CH, 1H), 1.62 (s, —CH3, 3H)
The obtained compound (a0-1-6) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHZ): δ (ppm)=10.71 (s, —OH, 1H), 6.92-7.74 (m, —Ar—, 3H), 6.62-6.70 (m, —CH═, 1H), 5.68-5.79 (m, —CH═CH—, ═CH2, 3H), 5.18 (d, ═CH2, 1H), 3.58 (s, ═CH, 1H), 1.62-2.35 (m, —(CH2) 3-, 6H)
The obtained compound (a0-1-7) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHz): δ (ppm)=10.72 (s, —OH, 1H), 6.87-7.66 (m, —Ar—, 3H), 6.60-6.75 (m, —CH═, 1H), 5.59-5.76 (m, —CH═CH—, ═CH2, 3H), 5.25 (d, ═CH2, 1H), 1.62-2.35 (m, —(CH2) 3-, —CH3, 9H)
The obtained compound (a0-1-8) was subjected to NMR measurement, and the structure thereof was identified based on the following data.
1H-NMR (DMSO-d6, 400 MHz): δ (ppm)=6.90-7.74 (m, —Ar—, 3H), 6.66-6.72 (m, —CH═, 1H), 5.90 (t, —CH═, 1H), 5.73 (d, ═CH2, 1H), 5.19 (d, ═CH2, 1H), 5.27-5.33 (m, ═CH2, 2H), 3.80 (s, —OCH3, 3H), 3.61 (s, ═CH, 1H), 1.62 (s, —CH3, 3H)
Each of polymer compounds (A1-1) to (A1-11) and polymer compounds (A2-1) to (A2-4) was produced by the following synthesis method using the above-described compounds (a0-1-1) to (a0-1-8), and a compound (a10-1pre), a compound (a10-2pre), a compound (a10-3pre), a compound (a5-1), a compound (a1-1), a compound (a1-2), a compound (a6-1), and a compound (a6-2) shown below.
10.0 g of the compound (a10-1pre), 15.0 g of the compound (a0-1-1), and 7.5 g of dimethyl azobis(isobutyrate) (V-601) as a polymerization initiator were dissolved in 50 g of methyl ethyl ketone (MEK), and the mixture was stirred at 70° C. for 5 hours in a nitrogen atmosphere. Thereafter, the reaction solution was cooled to room temperature to obtain a polymerization liquid containing the polymer compound (A1-1pre).
Next, 3.0 g of acetic acid and 60 g of methanol were added to the obtained polymerization liquid, and a deprotection reaction was carried out at 30° C. for 8 hours. After completion of the reaction, the obtained reaction solution was precipitated in 1200 g of a mixed solvent of methanol and water and washed. The obtained white solid substance was filtered and dried under reduced pressure overnight to obtain the target polymer compound (A1-1).
The weight-average molecular weight (Mw) of the obtained polymer compound (A1-1) in terms of standard polystyrene, determined by GPC measurement, was 6100, and the polydispersity (Mw/Mn) thereof was 1.56.
Further, the copolymer compositional ratio (ratio (molar ratio) between constitutional units in the structural formula) determined from the carbon 13 nuclear magnetic resonance spectrum (13C-NMR) was l/m=40/60.
Each of polymer compounds (A1-2) to (A1-11) and polymer compounds (A2-1) to (A2-4) was obtained by the same synthesis method (radical polymerization and deprotection reaction) as in [Synthesis of polymer compound (A1-1)] described above using the corresponding raw material monomers. The structure of each of the obtained polymer compounds is shown below.
With respect to the obtained polymer compounds, the copolymer compositional ratio (the ratio (molar ratio) between constitutional units derived from compounds which are monomers) of the polymer compound, determined by 13C-NMR, and the weight-average molecular weight (Mw) and the polydispersity (Mw/Mn) in terms of standard polystyrene, determined by GPC measurement, are collectively listed in Table 1.
Each of the components shown in Tables 2 and 3 was mixed and dissolved to prepare a resist composition of each Example.
In Tables 2 and 3, each abbreviation has the following meaning. The numerical values in the brackets are blending amounts (parts by mass).
A line-and-space pattern (hereinafter, referred to as “LS pattern”) was formed by the method for forming a resist pattern described below, and the sensitivity and the etching resistance were evaluated.
An 8-inch silicon substrate which had been subjected to a hexamethyldisilazane (HMDS) treatment was coated with each resist composition of each example using a spinner, and subjected to a pre-bake (PAB) treatment on a hot plate at a temperature of 110° C. for 60 seconds so that the 8-inch silicon substrate was dried, thereby forming a resist film having a film thickness of 50 nm.
Next, the resist film was subjected to drawing (light exposure) using an electron beam lithography apparatus JEOL JBX-9300FS (manufactured by JEOL Ltd.) at an acceleration voltage of 100 kV, to form an LS pattern having a line width of 50 nm and a pitch width of 100 nm.
Thereafter, a post exposure bake (PEB) treatment was performed thereon at 100° C. for 60 seconds.
Subsequently, alkali development was performed at 23° C. for 60 seconds using a 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution “NMD-3” (trade name, manufactured by TOKYO OHKA KOGYO CO., LTD.).
Thereafter, water rinsing was carried out with pure water for 15 seconds.
As a result, an LS pattern in which the line width was 50 nm and the space width was 50 nm in a ratio of 1:1 was formed in all the examples.
According to <<Formation of resist pattern>> described above, an optimum exposure amount Eop (μC/cm2) in which an LS pattern with a target size was formed was determined. The results are listed in the columns of “Eop (μC/cm2)” in Table 4.
Each resist film having a film thickness of 50 nm, which was obtained by performing a PAB treatment and drying in <<Formation of resist pattern>> described above, was subjected to a dry etching treatment using a dry etching device TCA-3822 (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) with CF4 gas for 60 seconds.
The residual film amount was determined from the film thicknesses of the resist film before and after the dry etching treatment.
Further, the residual film amount of the resist film formed of the resist composition of each example was obtained as a relative value in a case where the residual film amount of the resist film formed of the resist composition of Comparative Example 1 was set to 1.00, and the amount was listed in the columns of “etching resistance” in Table 4.
As the relative value increases, the residual film amount is relatively large, the film reduction is suppressed, and the etching resistance is high.
As shown in the results listed in Table 4, it was confirmed that in the resist compositions of Examples 1 to 11 to which the present invention was applied, the etching resistance was further improved and the high sensitivity was further achieved as compared with the resist compositions of Comparative Examples 1 and 2.
In the resist compositions of Comparative Examples 3 and 4, the resist compositions were not resolved even after the drawing (light exposure), the post exposure bake (PEB) treatment, and the alkali development were performed, and thus a predetermined LS pattern could not be formed (poor resolution).
While preferred embodiments of the present invention have been described and illustrated above, it should be understood that these are exemplary of the present invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the scope of the invention. The present invention is not limited by the description above, but is limited only by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-036436 | Mar 2022 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2023/009030 | 3/9/2023 | WO |
