Generally, the present invention relates to semiconductor devices, and, in particular, to semiconductor device having capacitors.
Capacitors may be a part of semiconductor devices. Examples of capacitors include, but not limited to, stacked capacitors, metal-insulator-metal (MIM) capacitors, trench capacitors and vertical-parallel-plate (VPP) capacitors. For devices with high capacity per area used, surface enhancement by means of trenches may be a preferred method. There may be practical limits for the trench depth. New methods are needed for further surface gain.
FIGS. 1 through 10A-D (10A through 10D) show a process for making a capacitor in accordance with an embodiment of the present invention;
FIGS. 12 through 21A-D show a process for making a capacitor in accordance with an embodiment of the present invention;
The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the invention. The various embodiments are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments.
FIGS. 1 through 10A-D show a method of making a capacitor 320 shown in
Referring to
The opening 214 may be formed as a hole or as trench. When the opening 214 is formed as a hole, the hole may have any lateral cross-sectional shape. Examples of lateral cross-sections for holes include substantially circular, substantially elliptical, substantially square and substantially rectangular.
Generally, the opening 214 may include a bottom surface and at least one sidewall surface (one or more sidewall surfaces). The bottom surface of the opening 214 may be formed over a conductive portion of the substrate 210.
The bottom surface 214B of the opening 214 has a first lateral dimension DX which may be in the X-direction and a second lateral dimension DY which may be in the Y-direction. In one or more embodiments DX may be substantially equal to DY. In one or more embodiments DX may be greater than DY. In one or more embodiments DX may be less than DY.
Examples of the lateral dimensions DX, DY are seen in
Referring to
In one or more embodiments, the lateral dimension DX of the opening 214 may be around 2 microns or less. In one or more embodiments, the depth DZ of the opening DZ may be around 30 microns or greater. In one or more embodiments, the depth DZ of the opening DZ may be around 40 microns or greater.
As an optional step in the formation of the capacitor structure, after the formation of the opening 214, a region of the substrate adjacent or proximate to the opening 214 may be n and/or p doped to form an n or p doped monocrystalline region adjacent or proximate to the opening 214. As explained below, this n or p doped monocrystalline region may be a portion of the first electrode of the capacitor structure.
Referring to
In one or more embodiments, the layer 220 may comprise a carbon material. In one or more embodiments, the layer 220 may consist essentially of a carbon material. The carbon material may be any material which includes carbon (C). In one or more embodiments, the carbon material may be any material that includes carbon atoms. In one or more embodiments, the carbon material may be molecular carbon. In one or more embodiments, the carbon material may be a carbon allotrope. Examples of carbon allotropes include, but are not limited to, diamond, graphite, amorphous carbon, buckministerfullerenes (such as buckyballs, carbon nanotudes and carbon nanobuds), glassy carbon, carbon nanofoam, lonsdaleite (hexagonal carbon), linear acetylenic carbon, chaoite, metallic carbon, hexagonite, and prismane C8.
In one or more embodiments, the carbon material may be a material selected from the group consisting of diamond, graphite, graphene, amorphous carbon, buckministerfullerenes, glassy carbon, carbon nanofoam, lonsdaleite (hexagonal carbon), linear acetylenic carbon, chaoite, metallic carbon, hexagonite, and prismane C8, and mixtures thereof. Other materials are also possible.
Hence, in one or more embodiments, the layer 220 may comprise or consist essentially of at least one material selected from the group consisting of diamond, graphite, graphene, amorphous carbon, buckministerfullerenes (such as buckyballs, carbon nanotudes and carbon nanobuds), glassy carbon, carbon nanofoam, lonsdaleite (hexagonal carbon), linear acetylenic carbon, chaoite, metallic carbon, hexagonite, prismane C8 and mixtures thereof. Other materials are also possible.
In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is dry removable. In one or more embodiments, the layer 220 may be formed of any material that can be removable without using a liquid. In one or more embodiments, the layer 220 may comprise or consist essentially of any material that is dry etchable. In one or more embodiments, the layer 220 may comprise or consist essentially a material that is etchable without using a liquid. In one or more embodiments, the layer 220 may comprise or consist essentially a material that is removable without using a liquid.
In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 200° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 300° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 350° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 400° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 500° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 600° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 650° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 650° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 700° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 750° C. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 800° C.
It is noted that, in one or more embodiments, a material which is stable at a particular temperature TEMP may also be stable at temperatures below TEMP. For example, a material which is stable at about 200° C. may also be stable at temperatures below about 200° C.
In one or more embodiments, the layer 220 may comprise or consist essentially of any material that is stable at a temperature of about 200° C. and also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 300° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 400° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 500° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 600° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 650° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 700° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 750° C. and is also dry removable. In one or more embodiments, the layer 220 may comprise or consist essentially of a material that is stable at a temperature of about 800° C. and is also dry removable.
In one or more embodiments, the stability of the material used for the layer 220 may be a thermal stability. In one or more embodiments, the layer 220 may comprise or consist essentially of a thermally stable material. In one or more embodiments, the layer 220 may comprise or consist essentially of a material which is thermally stable during the deposition or growth of the first conductive layer 230 (explained below).
In one or more embodiments, the thickness of the layer 220 may be about 1000 Angstroms or less. In one or more embodiments, the thickness of the layer 220 may be about 750 Angstroms or less. In one or more embodiments, the thickness of the layer 220 may be about 500 Angstroms or less. In one or more embodiments, the thickness of the layer 220 may be about 300 Angstroms or less.
Referring to
In one or more embodiments, the opening 214 may be a hole. Referring to
More generally, when the opening 214 is a hole, a sidewall spacer 222 may be formed which has a lateral cross-sectional shape that corresponds to the lateral cross-sectional shape of the opening 214. The spacer 222 may be tubular in shape. In one or more embodiments, the lateral cross-section of the spacer 222 may form a closed loop.
As noted, in one or more embodiments, the opening 214 may be a trench. In this case, the anisotropic etch of the layer 220 shown in
In one or more embodiments, the sidewall spacer(s) 222 may be dry removable. In one or more embodiments, the sidewall spacer(s) be removable without using a liquid. In one or more embodiments, the sidewall spacers 222 may be dry etchable. In one or more embodiments, the sidewall spacer(s) 222 may be etchable without using a liquid.
In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 200° C. In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 300° C. In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 400° C. In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 500° C. In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 600° C. In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 650° C. In one or more embodiments, the sidewall spacer(s) 222 may be stable at a temperature of about 700° C.
In one or more embodiments, the sidewall spacer may also be stable at temperatures below those indicated.
In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 200° C. In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 300° C. In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 400° C. In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 500° C. In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 600° C. In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 650° C. In one or more embodiments, the sidewall spacer(s) 222 may be dry removable and stable at a temperature of about 700° C.
In one or more embodiments, the sidewall spacer(s) may also be stable at temperatures below that indicated.
In one or more embodiments, the stability of the sidewall spacer(s) 222 may be a thermal stability. In one or more embodiments, the sidewall spacer(s) 222 should be able to withstand the temperatures of the deposition or growth process of the first conductive layer 230. In one or more embodiments, the sidewall spacer(s) 222 may be thermally stable during the deposition or growth of the first conductive layer 230 (described below).
Referring to
The first conductive layer 230 may be formed by a deposition process or by a growth process. In one or more embodiments, the first conductive layer 230 may be formed by a substantially conformal deposition process. Hence, the first conductive layer 230 may be substantially conformally deposited over the sidewall spacer(s) 222 within the opening 214. For example, the first conductive layer 230 may be substantially conformally deposited over the sidewall surface(s) 222S of the sidewall spacer(s) 222 as well as over the portion of the bottom surface 214B of opening 214 not covered by the sidewall spacer(s) 222. In one or more embodiments, the first conductive layer may be formed by a chemical vapor deposition process.
Referring to
In another embodiment, the deposition of first conductive layer 230 into the opening 214 need not be conformal and may at least partially fill the portion of the opening 214 interior to the sidewall spacer(s) 222.
In one or more embodiments, the first conductive layer 230 may be electrically coupled to at least a portion of the bottom surface of the opening 214.
In one or more embodiments, the first conductive layer 230 may comprise any conductive material. In one or more embodiments, the first conductive layer 230 may comprise a doped polysilicon. The doped polysilicon may be p-doped and/or n-doped. The doping may be performed in-situ or it may be performed, for example, by some type of ion implantation process or some other type of suitable process.
In one or more embodiments, the first conductive layer 230 may comprise a metallic material such as a pure metal or a metal alloy. The first conductive layer 230 may also be a composite or heterogeneous mixture of two or more conductive materials. The first conductive layer 230 may be formed as a layered stack of two or more layers (e.g. sub-layers of the first conductive layer 230). Each layer (e.g. sub-layer of the first conductive layer 230) of the stack may comprise a different conductive material.
In one or more embodiments, the first conductive layer 230 may be deposited or grown in a conductive state. In one or more embodiments, the first conductive layer 230 may not be deposited or grown in a conductive state. Instead, in one or more embodiments, the first conductive layer 230 may be made conductive (for example, by a doping process) after it is deposited or grown. For example, an undoped polysilicon material (e.g. undoped polysilicon) may first be deposited and then this polysilicon material may be doped after deposition by, for example, an implantation process or any other type of suitable process (such as a diffusion process). In one or more embodiments, the first conductive layer 230 may be made conductive, for example, after it is etched to form the first conductive structure 232 as shown in
Referring to
The etching of the first conductive layer 230 forms a remaining portion of first conductive layer 230 which may also be referred to as first conductive structure 232. When the opening 214 is a hole, the first conductive structure 232 shown in
Referring to
The sidewall spacer(s) 222 may then be removed from the structure shown in
In one or more embodiments, the dry etch process (for example, an ashing process such as a carbon ashing process) may be performed without a plasma. The semiconductor structure may be heated (for example, in a furnace such as an ashing furnace) to a temperature at or above about 600° C. In one or more embodiments, the temperature may be at or above about 700° C. The pressure within the furnace may be kept at about atmospheric pressure or even below atmospheric pressure. In some embodiments, the pressure may be about 10 mbar or greater. In some embodiments, the pressure may be about 25 mbar or greater. In some embodiments, the pressure may be about 100 mbar or less. In some embodiments, the etching may be performed in a batch furnace. In some embodiments, the etching may be performed in a batch furnace. In some embodiments, the etching may be performed as a rapid thermal process.
The semiconductor structure shown in
In one or more embodiments, the dry etch process (e.g. the carbon ashing process) may use a plasma. The plasma may, for example, be an oxygen plasma and/or a hydrogen plasma. In addition to the use of the plasma, fluorine may be introduced to enhance the etching of the plasma. In one or more embodiments, the plasma etching process may be performed at temperatures of about 300° C. or greater. In one or more embodiments, the plasma etching process may be performed at temperatures of about 400° C. or greater. In one or more embodiments, the plasma etching process may be performed at temperatures of about 500° C. or greater.
Hence, the oxygen or hydrogen plasma may serve as a reactive ion species. The reactive ion species may combine with the sidewall spacer material (e.g. a carbon material such as graphite) to form an ash which may be removed with the use of a vacuum pump. Typically, a monotomic (single atom) oxygen plasma may be created by exposing oxygen gas (O2) or the hydrogen gas (H2) to non-ionizing radiation. This process may be done under a vacuum in order to create a plasma.
In some embodiments, the plasma ashing process may be performed at low pressure. In some embodiments, the pressure may be sub-atmospheric. In some embodiments, the pressure may be about 100 mbar or less. In some embodiments, the pressure may be about 10E−3 mbar or greater. In some embodiments, the plasma power may about 500 Watts or greater. In some embodiments, the plasma power may be about 600 Watts or greater. In some embodiments, the plasma power may be about 700 Watts or greater. In some embodiments, the plasma power may be about 1500 Watts or less. In some embodiments, a rapid thermal process may be used.
Referring to
Referring to
Referring to
Referring to
Referring to
The dielectric layer 240 may be formed by a deposition process or by a growth process. The deposition process may be a substantially conformal deposition process. The dielectric layer 240 may thus be substantially conformally deposited over the exposed sidewall and bottom surfaces of the opening 214 as well as over the surfaces of the first conductive structure 232. The dielectric layer 240 may line the exposed surfaces of the opening 214 as well as the exposed surfaces of the first conductive structure 232.
The dielectric layer 240 may comprise any dielectric material. Examples include oxides (such as silicon oxide), nitrides (such as silicon nitride), oxynitrides (such as silicon oxynitride), or mixtures thereof. The dielectric layer 240 may also comprise a high-k material.
Referring to
The second conductive layer 250 may be formed by any type of deposition or growth process. In one or more embodiments, the deposition process may be a substantially conformal deposition process.
The second conductive layer 250 may comprise any conductive material. In one or more embodiments, the second conductive layer 250 may comprise a doped polysilicon. The doped polysilicon may be p-doped and/or n-doped. The doping may be performed in-situ or it may be performed, for example, by some type of implantation process.
In one or more embodiments, the second conductive layer 250 may comprise a metallic material such as a pure metal or a metal alloy. The second conductive layer 250 may also be a composite or heterogeneous mixture of two or more conductive materials. The second conductive layer 250 may be formed as a layered stack of two or more layers (e.g. sub-layers of the second conductive layer 250). Each layer (e.g. sub-layer of the second conductive layer) of the stack may comprise a different conductive material.
In one or more embodiments, the second conductive layer 250 may be deposited or grown in a conductive state. In one or more embodiments, the second conductive layer 250 may not be deposited or grown in a conductive state. Instead, the second conductive layer 250 may be made conductive (for example, by a doping process) after it is deposited or grown. For example, an undoped polysilicon material (e.g. undoped polysilicon) may be deposited and then this polysilicon material may be doped after deposition by an implantation process. The second conductive layer 250 may be made conductive any time after it is formed. For example, in one or more embodiments, it may be made conductive after it is deposited or grown but before the structure 252 shown in
Referring to
The etching and/or chemical mechanical polishing process of the second conductive layer 250 removed a portion of second conductive layer 250 and leaves a remaining portion of second conductive layer 250 shown in
In one or more embodiment, substantially all of the second conductive structure 252 may be formed within the opening 214. In one or more embodiments, at least a portion of the second conductive structure 214 may be formed above the top surface of the substrate 210.
In one or more embodiments, the opening 214 may be a hole. Referring to
Referring to
More generally, when the opening 214 is a hole, the first extension 252E1 may be tubular in shape where the cross-section of the extension 252E1 may correspond to the cross-section of the opening 214. In one or more embodiments, a tubular extension may have a lateral cross-section in the form of a closed loop.
In one or more embodiments, the first conductive structure 232 may have one or more extensions 232E (and possibly two or more extensions 232E). Each of the extensions may be substantially vertically disposed. Each may be oriented upward. Each may be spacedly disposed from the other. The extensions 232E may each be electrically coupled to a base region 232B. The base regions 232B may be electrically coupled to the substrate 210 (e.g. a conductive portion of the substrate 210). In another embodiment, the extensions 232E may each be electrically coupled to the substrate (e.g. a conductive portion of the substrate 210) without the base region 232B.
In one or more embodiments, the second conductive structure 252 may have one or more extensions 252E (and possibly two or more extensions 252E). Each of the extensions 252E may be substantially vertically disposed. Each may be oriented downward. Each may be spacedly disposed from the other. Each of the extensions 252E may be electrically coupled to a base region 252B.
The extensions 232E and the extensions 252E may be arranged so that they are alternatingly disposed.
In one or more embodiments, at least one of the extensions 232E may have a lateral thickness which is less than that which can be achieved using photolithography. In one or more embodiments, the lateral thickness may be less than about 500 Angstroms. In one or more embodiments, the lateral thickness may be less than about 400 Angstroms. In one or more embodiments, the lateral thickness may be less than about 300 Angstroms. In one or more embodiments, the lateral thickness may be less than about 200 Angstroms. In one or more embodiments, the lateral thickness may be less than about 150 Angstroms. In one or more embodiments, the lateral thickness may be less than about 100 Angstroms. An example of a lateral thickness of an extension 232E is shown as lateral thickness TH1 of extension 232E in
In one or more embodiments, at least one of the extensions 252E may have a lateral thickness which is less than that which can be achieved using photolithography. In one or more embodiments, the lateral thickness may be less than about 500 Angstroms. In one or more embodiments, the lateral thickness may be less than about 400 Angstroms. In one or more embodiments, the lateral thickness may be less than about 300 Angstroms. In one or more embodiments, the lateral thickness may be less than about 200 Angstroms. In one or more embodiments, the lateral thickness may be less than about 150 Angstroms. In one or more embodiments, the lateral thickness may be less than about 100 Angstroms. An example of a lateral thickness of an extension 252E is shown as lateral thickness TH2 of extension 252E1 in
The semiconductor structures 310 shown in
The capacitor 320 comprises a first capacitor electrode, a second capacitor electrode and a capacitor dielectric between the first and second capacitor electrodes. The first capacitor electrode of capacitor 320 comprises at least the first conductive structure 232. In one or more embodiments, the first capacitor electrode may further comprise at least a portion (such as a conductive portion) of the substrate 210. This portion of the substrate may be a portion which is adjacent or proximate to the opening 214. This adjacent or proximate portion of the substrate 210 may be a conductive portion of the substrate. It may be an n and/or p doped monocrystalline silicon material. The first conductive structure 232 may be electrically coupled to the bottom surface of the opening 214. The first conductive structure 232 may be electrically coupled to the conductive portion of the substrate.
The capacitor 310 may further comprise a capacitor dielectric. The capacitor dielectric comprises the dielectric layer 240.
The second capacitor electrode may comprise at least the second conductive structure 252.
Another embodiment of the invention is shown in
In one or more embodiments, the first conductive structure 232 (as hence the first electrode) may include at least one upwardly extending vertical extension (for example, N where N≧1) while the second conductive structure 252 may include a plurality of downwardly extending vertical extensions (for example, N+1 where N≧1).
Another embodiment of a capacitor of the present invention is the capacitor 320 shown in
The processing steps shown in
Referring to
In one or more embodiments, the first conductive layer 230 may be deposited or grown in a conductive state. In one or more embodiments, the first conductive layer 230 may not be deposited or grown in a conductive state and it may be made conductive in a later processing step. As an example, the first conductive layer 230 may be deposited as undoped polysilicon and then doped in a later processing step.
Referring to
Referring to
After the removal of the sidewall spacer(s) 222, one or more gaps 234 remains between the first conductive structure 232 and the sidewall surface(s) 214S of the opening 214. The first conductive structure 232 may have a top surface 232T. The top surface 232T may be at or below the top surface of the substrate 210.
Referring to
Referring to
In one or more embodiments, the second conductive layer 250 may be deposited or grown in a conductive state. In one or more embodiments, the second conductive layer 250 may not be deposited or grown in a conductive state but may be made conductive in a later processing step. For example, the second conductive layer may be deposited as undoped polysilicon and then doped at a later processing step.
Referring to
The second capacitor electrode comprises at least the second conductive structure 252. The second conductive structure 252 may include a base portion 252B. The second conductive structure 252 may further include one or more extensions 252E (and possibly two or more extensions 252E). The extension(s) 252E may be substantially vertically disposed.
The capacitor dielectric comprises at least the dielectric layer 240. The first conductive structure 232 shown in
When the opening 214 is a hole, the second conductive structure 252 may be in the shape of an upside down cup-structure having a base portion 252B and a downward extending vertical extension 252E. Generally, when the opening 214 is a hole, the extension 252E may be tubular in shape and may have a cross-section taking the shape of the opening 214. Hence, in the case in which the lateral cross-section of the opening 214 is in the shape of a substantially circular hole, the extension 252E may be substantially cylindrically shaped. When the opening 214 is a trench, the conductive structure 252 may be an upside down U-shape structure having a base portion 252B and extensions 252E which may be in the form of two spacedly disposed extensions 252E1 and 252E2 which may each be substantially planar.
The second conductive structure 252 may include a base portion 252B. The second conductive structure 252 may include one or more extensions 252E. The extensions 252E may be substantially vertically disposed. The extensions 232E may be oriented downward and may be electrically coupled to the base portion 232B. The base portion 252B may be electrically coupled to another conductive element.
Referring to the embodiments of the capacitors 320 shown, for example, in
In one or more embodiments, the first and second conductive layers (for example, first conductive layer 230 and second conductive layer 250 described herein), the first and second conductive structures (for example, first conductive structure 232 and second conductive structure 252) as well as any other conductive layers, regions or structures described herein may comprise any conductive material. In one or more embodiments, the conductive material may comprise a doped polysilicon. The doped polysilicon may be p-doped and/or n-doped. The doping may be performed in-situ or it may be performed, for example, by some type of ion implantation process, diffusion process or any other type of suitable process. Generally, the doping may occur at any point in the manufacturing process.
In one or more embodiments, the conductive material may comprise a metallic material. The metallic material may comprise a pure metal. The metallic material may comprise a metal alloy. The metallic material may comprise, without limitation, one or more periodic table elements from the group consisting of Al (aluminum), Cu (copper), Au (gold), Ag (silver), W (tungsten), Ti (titanium), and Ta (tantalum).
As possible examples, the conductive material may comprise one or more materials selected from the group consisting of pure aluminum, aluminum alloy, pure copper, copper alloy, pure gold, gold alloy, pure silver, silver alloy, pure tungsten, tungsten alloy, pure titanium, titanium alloy, pure tantalum, and tantalum alloy. It is understood that the pure metals may include small amounts of trace impurities. As additional examples, the conductive material may comprise a nitride. The metal nitride may be a refractory metal nitride. Examples of conductive material which may be used include, but not limited to, TiN, TaN and WN.
The conductive material may also comprise a conductive polymer. The conductive material may comprise a non-metallic conductive material. In one or more embodiments, the material may be doped. The doping may, for example, be in-situ or it may be performed by an implantation process.
The conductive material may also be a composite or heterogeneous mixture of two or more conductive materials. In one or more embodiments, conductive layers and structures may be formed as a layered stack of two or more layers. Each layer may comprise a different conductive material.
As noted above, in one or more embodiments, one or more of the conductive layers or structures described herein may not be conductive when deposited or grown but may be made conductive after deposition or growth.
In one or more embodiments, the layers used to form the capacitor electrodes (for example, the layer 230 and the layer 250 described above) may comprise any suitable electrode material for a capacitor electrode.
The dielectric layers described herein may comprise any dielectric material. In one or more embodiments, the dielectric material may include an oxide, a nitride, an oxynitride and combinations thereof. Examples of possible oxides include, but not limited to silicon oxide, aluminum oxide, hafnium oxide, tantalum oxide, and combinations thereof. Examples of possible nitrides include, but not limited to, silicon nitride. Examples of possible oxynitrides include, but not limited to, silicon oxynitride.
The dielectric material may comprise a high-k material. The high-k material may have a dielectric constant greater than that of silicon dioxide. In one or more embodiments, the high-k material may have a dielectric constant greater that 3.9. In one or more embodiments, the dielectric may be a gas. In one or more embodiments, the dielectric may be air. In one or more embodiments, the dielectric may be a vacuum.
It is noted that in one or more embodiments, the techniques described herein may provide a capacitor with a higher specific capacitance. It is noted that in one or more embodiments, the techniques described herein may provide a capacitor with a higher surface area.
One or more embodiments may relate to a method of making a capacitor, comprising: providing a substrate; forming an opening within the substrate; forming a sidewall spacer over a sidewall surface of the opening; forming a first conductive layer within the opening after forming the sidewall spacer; removing the sidewall spacer; forming a dielectric layer over the first conductive layer within the opening; and forming a second conductive layer over the dielectric layer within the opening. In one or more embodiments, the substrate may be a semiconductor substrate. In one or more embodiments, the capacitor may be a trench capacitor. In one or more embodiments, the substrate may be semiconductor substrate.
One or more embodiments may relate to a method of making a trench capacitor, comprising: providing a substrate; forming an opening within the substrate; forming a sidewall spacer over a sidewall surface of the opening; forming a first conductive layer within the opening after forming the sidewall spacer; removing the sidewall spacer; forming a dielectric layer over the first conductive layer within the opening; and forming a second conductive layer over the dielectric layer within the opening. In one or more embodiments, the substrate may be a semiconductor substrate.
One or more embodiments may relate to a method of making a capacitor, comprising: forming an opening within a substrate; forming a first layer over a sidewall of the opening; forming a first electrode material within the opening after forming the layer; removing the first layer after forming the first electrode material; forming a dielectric material over the first electrode material within the opening; and forming a second electrode material over the dielectric material within the opening. In one or more embodiments, the capacitor may be a trench capacitor. In one or more embodiments, the substrate may be a semiconductor substrate. In one or more embodiments, the first layer may comprise a sidewall spacer. In one or more embodiments, the first layer may comprise at least one sidewall spacer. In one or more embodiments, the first layer may be a sidewall spacer.
One or more embodiments may relate to a semiconductor device, comprising: a substrate comprising an opening; a capacitor at least partially disposed within the opening, the capacitor including a first conductive structure disposed within the opening, a dielectric layer overlying the first conductive structure within the opening and a second conductive structure overlying the dielectric layer within the opening, the first conductive structure and/or the second conductive structure comprising at least one substantially vertical extension, the extension having a lateral thickness less than about 500 Angstroms.
The disclosure herein is presented in the form of detailed embodiments described for the purpose of making a full and complete disclosure of the present invention, and that such details are not to be interpreted as limiting the true scope of this invention as set forth and defined in the appended claims.