Patent Application
20230313034
This application claims priority to and benefits of Korean Patent Application No. 10-2022-0041905 under 35 U.S.C. § 119, filed on Apr. 4, 2022, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.
Embodiments relate to a method of preparing a metal oxide composition, a light-emitting device using a metal oxide composition prepared thereby, and an electronic apparatus including the light-emitting device.
Light-emitting devices are devices that convert electrical energy into light energy. Examples of such light-emitting devices include organic light-emitting devices in which a light-emitting material is an organic material, and quantum dot light-emitting devices in which the light-emitting material is a quantum dot.
In a light-emitting device, a first electrode is arranged on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode are sequentially arranged on the first electrode. Holes provided from the first electrode move toward the emission layer through the hole transport region, and electrons provided from the second electrode move toward the emission layer through the electron transport region. Carriers, such as holes and electrons, recombine in the emission layer to produce excitons. These excitons transition from an excited state to a ground state, thereby generating light.
It is to be understood that this background of the technology section is, in part, intended to provide useful background for understanding the technology. However, this background of the technology section may also include ideas, concepts, or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to a corresponding effective filing date of the subject matter disclosed herein.
Embodiments include a method of preparing a metal oxide composition, a light-emitting device using a metal oxide composition prepared thereby, and an electronic apparatus including the light-emitting device.
Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the embodiments of the disclosure.
Embodiments provide a method of preparing a metal oxide composition, which may include:
According to an embodiment, the first metal oxide particle may be represented by Formula 1, which is explained below.
According to an embodiment, the first metal oxide particle may include Zn.
According to an embodiment, the preparing of the first metal oxide particle may include:
According to an embodiment, the metal oxide precursor may include a metal acetate compound represented by Formula 3, which is explained below.
According to an embodiment, the forming of the first metal oxide particle may be performed in a range of about 30 minutes to about 2 hours.
According to an embodiment, the halide compound may include a metal halide compound, an ammonium halide compound, a tetraalkylammonium halide compound, or any combination thereof.
According to an embodiment, the halide compound may include a metal halide compound represented by Formula 4, which is explained below.
According to an embodiment, the halide compound may be added in an amount in a range of about 0.01 parts by weight to about 30 parts by weight, based on 100 parts by weight of the first metal oxide particle.
According to an embodiment, the forming of the metal oxide particle may be performed at a temperature equal to or less than about 30° C.
According to an embodiment, the forming of the metal oxide particle may not include heat-treating.
According to an embodiment, an average particle diameter (D50) of the metal oxide particle may be in a range of about 1 nm to about 50 nm.
Embodiments provide a light-emitting device which may include a first electrode, a second electrode facing the first electrode, an interlayer between the first electrode and the second electrode and including an emission layer, and a metal oxide layer formed using a metal oxide composition prepared by the method.
According to an embodiment, the emission layer may include a quantum dot.
According to an embodiment, the quantum dot may include a Group II-VI semiconductor compound, a Group III-V semiconductor compound, a Group III-VI semiconductor compound, a Group I-III-VI semiconductor compound, a Group IV-VI semiconductor compound, a Group IV element or compound, or any combination thereof.
According to an embodiment, the first electrode may be an anode,
According to an embodiment, no other layer may be arranged between the emission layer and the metal oxide layer.
Embodiments provide an electronic apparatus which may include the light-emitting device.
According to an embodiment, the electronic apparatus may further include a thin-film transistor,
According to an embodiment, the electronic apparatus may further include a color filter, a quantum dot color conversion layer, a touch screen layer, a polarizing layer, or any combination thereof.
It is to be understood that the embodiments above are described in a generic and explanatory sense only and not for the purpose of limitation, and the disclosure is not limited to the embodiments described above.
The above and other aspects and features of the disclosure will be more apparent by describing in detail embodiments thereof with reference to the accompanying drawings, in which:
The disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. This disclosure may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
In the drawings, the sizes, thicknesses, ratios, and dimensions of the elements may be exaggerated for ease of description and for clarity. Like numbers refer to like elements throughout.
In the description, it will be understood that when an element (or region, layer, part, etc.) is referred to as being “on”, “connected to”, or “coupled to” another element, it can be directly on, connected to, or coupled to the other element, or one or more intervening elements may be present therebetween. In a similar sense, when an element (or region, layer, part, etc.) is described as “covering” another element, it can directly cover the other element, or one or more intervening elements may be present therebetween.
In the description, when an element is “directly on,” “directly connected to,” or “directly coupled to” another element, there are no intervening elements present. For example, “directly on” may mean that two layers or two elements are disposed without an additional element such as an adhesion element therebetween.
It will be understood that the terms “connected to” or “coupled to” may include a physical or electrical connection or coupling.
As used herein, the expressions used in the singular such as “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, “A and/or B” may be understood to mean “A, B, or A and B.” The terms “and” and “or” may be used in the conjunctive or disjunctive sense and may be understood to be equivalent to “and/or”.
In the specification and the claims, the term “at least one of” is intended to include the meaning of “at least one selected from the group of” for the purpose of its meaning and interpretation. For example, “at least one of A and B” may be understood to mean “A, B, or A and B.” When preceding a list of elements, the term, “at least one of,” modifies the entire list of elements and does not modify the individual elements of the list.
It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, a first element could be termed a second element without departing from the teachings of the disclosure. Similarly, a second element could be termed a first element, without departing from the scope of the disclosure.
The spatially relative terms “below”, “beneath”, “lower”, “above”, “upper”, or the like, may be used herein for ease of description to describe the relations between one element or component and another element or component as illustrated in the drawings. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the drawings. For example, in the case where a device illustrated in the drawing is turned over, the device positioned “below” or “beneath” another device may be placed “above” another device. Accordingly, the illustrative term “below” may include both the lower and upper positions. The device may also be oriented in other directions and thus the spatially relative terms may be interpreted differently depending on the orientations.
The terms “about” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the recited value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the recited quantity (i.e., the limitations of the measurement system). For example, “about” may mean within one or more standard deviations, or within ±20%, ±10%, or ±5% of the stated value.
It should be understood that the terms “comprises,” “comprising,” “includes,” “including,” “have,” “having,” “contains,” “containing,” and the like are intended to specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof in the disclosure, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.
Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an ideal or excessively formal sense unless clearly defined in the specification.
The term “Group II” as used herein may include a Group IIA element and a Group IIB element on the IUPAC periodic table, and examples of the Group II element may include Cd, Mg, and Zn, but embodiments are not limited thereto.
The term “Group III” as used herein may include a Group IIIA element and a Group IIIB element on the IUPAC periodic table, and examples of the Group III element may include Al, In, Ga, and TI, but embodiments are not limited thereto.
The term “Group IV” as used herein may include a Group IVA element and a Group IVB element on the IUPAC periodic table, and examples of the Group IV element may include Si, Ge, and Sn, but embodiments are not limited thereto.
The term “Group V” as used herein may include a Group VA element on the IUPAC periodic table, and examples of the Group V element may include N, P, As, Sb, and Bi, but embodiments are not limited thereto.
The term “Group VI” as used herein may include a Group VIA element on the IUPAC periodic table, and examples of the Group VI element may include O, S, Se, and Te, but embodiments are not limited thereto.
The term “metal” as used herein may include a metalloid such as Si. Examples of the metalloid may include B, Si, Ge, As, Sb, Te, and the like.
Hereinafter, a method of preparing a metal oxide composition according to embodiments will be described.
The method of preparing a metal oxide composition may include: preparing a first metal oxide particle; and forming a metal oxide particle by adding a halide compound to the first metal oxide particle, and treating the first metal oxide particle with the halide compound at a temperature equal to or less than 60° C.
In an embodiment, the first metal oxide particle may be represented by Formula 1:
MxOy [Formula 1]
In Formula 1,
In an embodiment, the first metal oxide particle may include Zn.
In an embodiment, the first metal oxide particle may include Zn, and a molar number of Zn with respect to a total molar number of metals included in the first metal oxide particle may be equal to or greater than about 50 mol %.
In embodiments, the first metal oxide particle may be represented by Formula 2:
Zn1-zNzO [Formula 2]
In Formula 2,
In an embodiment, the preparing of the first metal oxide particle may include:
In an embodiment, the metal oxide precursor may include a metal acetate compound represented by Formula 3:
In Formula 3,
In embodiments, the metal oxide precursor may include zinc acetate dihydrate, magnesium acetate tetrahydrate, or a combination thereof.
In an embodiment, the solvent may include dimethylsulfoxide (DMSO).
In an embodiment, the oxidizing agent may include tetramethylammonium hydroxide pentahydrate (TMAH).
In an embodiment, the first metal oxide particle may be ZnO, ZnMgO, or a combination thereof.
In an embodiment, the forming of the first metal oxide particle may be performed in a range of about 30 minutes to about 2 hours. For example, the forming of the first metal oxide particle may be performed by adding the oxidizing agent to the precursor composition and stirring the mixture in a range of about 30 minutes to about 2 hours.
In an embodiment, the forming of the first metal oxide particle may be performed in a range of about 45 minutes to about 1 hour and 30 minutes.
A metal oxide particle may be formed by adding a halide compound to the first metal oxide particle and treating the first metal oxide particle with the halide compound at a temperature equal to or less than about 60° C.
In an embodiment, the halide compound may include a metal halide compound, an ammonium halide compound, a tetraalkylammonium halide compound, or any combination thereof.
In an embodiment, the halide compound may include a metal halide compound represented by Formula 4:
Mn+(X−)n [Formula 4]
In Formula 4,
In an embodiment, the metal halide compound may include Zn.
In embodiments, the metal halide compound may include ZnF2, ZnCl2, or a combination thereof.
In an embodiment, the first metal oxide particle and the metal halide compound may include a same metal atom.
In embodiments, a metal atom of the first metal oxide particle and a metal atom of the metal halide compound may each include a Zn atom.
In an embodiment, the halide compound may be added in an amount in a range of about 0.01 parts by weight to about 30 parts by weight, based on 100 parts by weight of the first metal oxide particle.
In embodiments, the halide compound may be added in an amount in a range of about 0.1 part by weight to about 15 parts by weight, based on 100 parts by weight of the first metal oxide particle.
In an embodiment, the forming of the metal oxide particle may be performed at a temperature equal to or less than about 30° C.
In an embodiment , the forming of the metal oxide particle may be performed at a temperature in a range of about −15° C. to about 60° C. For example, the forming of the metal oxide particle may be performed at a temperature in a range of about −15° C. to about 30° C. For example, the forming of the metal oxide particle may be performed at a temperature in a range of about −10° C. to about 60° C. As another example, the forming of the metal oxide particle may be performed at a temperature in a range of about −10° C. to about 30° C.
In an embodiment, the forming of the metal oxide particle may be performed in a range of about 5 hours to about 20 hours.
In embodiments, the forming of the metal oxide particle may be performed in a range of about 7 hours to about 15 hours.
In an embodiment, the forming of the metal oxide particle may not include heat-treating. Accordingly, aggregation of the metal oxide particle may be prevented.
In an embodiment, an average particle diameter (D50) of the metal oxide particle may be in a range of about 1 nm to about 50 nm. In embodiments, the average particle diameter (D50) of the metal oxide particle may be in a range of about 5 nm to about 15 nm.
Since a method of preparing a metal oxide composition according to the disclosure includes treating a prepared first metal oxide particle with a halide compound at a temperature equal to or less than about 60° C., defects on a surface of a metal oxide particle included in a prepared metal oxide composition may be prevented. Accordingly, a light-emitting device manufactured using the metal oxide composition may have improved driving voltage, efficiency, and lifespan.
In case that an electron transport layer that is adjacent to an emission layer including a quantum dot is formed using the metal oxide composition, since surface defects of the metal oxide particle are prevented, charge loss due to the surface defects may be prevented, and thus, the driving voltage, efficiency, and lifespan of a manufactured light-emitting device (for example, a quantum dot light-emitting device) may be improved.
Provided is a light-emitting device which may include: a first electrode; a second electrode facing the first electrode; an interlayer between the first electrode and the second electrode and including an emission layer; and a metal oxide layer formed using a metal oxide composition prepared by the method described above.
In embodiments, the emission layer may include a quantum dot.
In the specification, a quantum may be a crystal of a semiconductor compound, and may include any material capable of emitting light of various emission wavelengths according to a size of the crystal.
The quantum dot in the emission layer may include a Group II-VI semiconductor compound, a Group III-V semiconductor compound, a Group III-VI semiconductor compound, a Group I-III-VI semiconductor compound, a Group IV-VI semiconductor compound, a Group IV element or compound, or any combination thereof.
Examples of the Group II-VI semiconductor compound may include: a binary compound, such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, or MgS; a ternary compound, such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, or MgZnS; a quaternary compound, such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, or HgZnSTe; or any combination thereof.
Examples of the Group III-V semiconductor compound may include: a binary compound, such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, or InSb; a ternary compound, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, or InPSb; a quaternary compound, such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, or InAlPSb; or any combination thereof. In an embodiment, the Group III-V semiconductor compound may further include a Group II element. Examples of the Group III-V semiconductor compound further including a Group II element may include InZnP, InGaZnP, InAlZnP, and the like.
Examples of the Group III-VI semiconductor compound may include: a binary compound, such as GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2S3, In2Se3, or InTe; a ternary compound, such as InGaS3 or InGaSe3; or any combination thereof.
Examples of the Group I-III-VI semiconductor compound may include: a ternary compound, such as AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2, or AgAlO2; or any combination thereof.
Examples of the Group IV-VI semiconductor compound may include: a binary compound, such as SnS, SnSe, SnTe, PbS, PbSe, or PbTe; a ternary compound, such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, or SnPbTe; a quaternary compound, such as SnPbSSe, SnPbSeTe, or SnPbSTe; or any combination thereof.
The Group IV element or compound may include: a single element material, such as Si or Ge; a binary compound, such as SiC or SiGe; or any combination thereof.
Each element included in a multi-element compound such as the binary compound, the ternary compound, and the quaternary compound may be present at a uniform concentration or non-uniform concentration in a particle.
In an embodiment, the quantum dot may have a single structure in which the concentration of each element in the quantum dot is uniform, or a core-shell dual structure. For example, a material included in the core and a material included in the shell may be different from each other.
In an embodiment, the core may include at least one of Zn, Te, Se, Cd, In, and P. For example, the core may include InP, InZnP, ZnSe, ZnTeS, ZnSeTe, or any combination thereof.
The shell of the quantum dot may serve as a protective layer that prevents chemical degeneration of the core to maintain semiconductor characteristics, and/or as a charging layer that imparts electrophoretic characteristics to the quantum dot. The shell may be a single layer or a multi-layer. The interface between the core and the shell may have a concentration gradient in which the concentration of an element existing in the shell decreases toward the center of the core.
Examples of the shell of the quantum dot may include an oxide of metal, metalloid, or non-metal, a semiconductor compound, or any combination thereof. Examples of the oxide of metal, metalloid, or non-metal may include: a binary compound, such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, or NiO; a ternary compound, such as MgAl2O4, CoFe2O4, NiFe2O4, or CoMn2O4; or any combination thereof. Examples of the semiconductor compound may include, as described herein, a Group II-VI semiconductor compound, a Group III-V semiconductor compound, a Group III-VI semiconductor compound, a Group I-III-VI semiconductor compound, a Group IV-VI semiconductor compound, or any combination thereof. For example, the semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, ZnSeTe, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, or any combination thereof.
In an embodiment, the shell may have a composition different from the composition of the core, and the shell may include ZnS, ZnSe, ZnSeS, ZnTeS, ZnSeTe, or any combination thereof.
The quantum dot may have a full width of half maximum (FWHM) of a spectrum of an emission wavelength of about 45 nm or less. For example, the quantum dot may have a FWHM of a spectrum of an emission wavelength equal to or less than about 40 nm. As another example, the quantum dot may have a FWHM of a spectrum of an emission wavelength equal to or less than about 30 nm. In case that the FWHM of the quantum dot is within this range, color purity or color reproducibility may be improved. Since the light emitted through the quantum dot is emitted in all directions, the viewing angle of light may be improved.
In an embodiment, an average particle diameter of the quantum dot may be in a range of about 1 nm to about 20 nm. In case that the average particle diameter of the quantum dot is within this range, specific behavior as a quantum dot may be achieved, and excellent dispersibility in a composition may be obtained. The quantum dot may be a spherical, pyramidal, multi-arm, or cubic nanoparticle, a nanotube, a nanowire, a nanofiber, or a nanoplate.
Since the energy band gap may be adjusted by controlling the size of the quantum dot, light having various wavelength bands may be obtained from an emission layer including the quantum dot. Accordingly, by using quantum dots of different sizes, a light-emitting device that emits light of various wavelengths may be implemented. The size of the quantum dot may be selected to emit red, green and/or blue light. The size of the quantum dot may be configured to emit white light by a combination of light of various colors.
The quantum dot may be synthesized by a wet chemical process, a metal organic chemical vapor deposition process, a molecular beam epitaxy process, or any process similar thereto.
The wet chemical process is a method including mixing a precursor material with an organic solvent and growing a quantum dot particle crystal. In case that the crystal grows, the organic solvent naturally acts as a dispersant coordinated on the surface of the quantum dot crystal and controls the growth of the crystal so that the growth of quantum dot particles may be controlled through a process which is more readily performed than vapor deposition methods, such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE), and which requires low costs.
The emission layer may include a monolayer of quantum dots. For example, the emission layer may include a monolayer of quantum dots from about 2 layers to about 20 layers.
A thickness of the emission layer may be in a range of about 5 nm to about 200 nm. For example, a thickness of the emission layer may be in a range of about 10 nm to about 150 nm. As another example, a thickness of the emission layer may be in a range of about 10 nm to about 100 nm.
For example, the metal oxide layer may be a layer formed using a metal oxide composition prepared by the method of preparing the same according to embodiments. The metal oxide layer may be formed by an inkjet process.
In an embodiment, the first electrode may be an anode, the second electrode may be a cathode, the light-emitting device may further include a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode, and the hole transport region or the electron transport region may include the metal oxide layer.
The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof. The metal oxide layer may be at least one of the hole injection layer, the hole transport layer, the emission auxiliary layer, and the electron blocking layer.
The electron transport region may include at least one of a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, and an electron injection layer. The metal oxide layer may be at least one of the buffer layer, the hole blocking layer, the electron transport layer, and the electron injection layer.
In an embodiment, the electron transport region may include the metal oxide layer.
In an embodiment, the electron transport region may include an electron transport layer, and the electron transport layer may include the metal oxide layer.
In an embodiment, the metal oxide layer may be formed adjacent to the emission layer. For example, after forming the emission layer, the metal oxide layer may be formed on the emission layer. For example, the metal oxide layer may be directly disposed on the emission layer.
In an embodiment, the emission layer may include a quantum dot, and in case that a metal oxide layer is formed on the emission layer including the quantum dot by using the metal oxide composition described above, damage to a surface of the quantum dot may be reduced, and thus, a quantum dot light-emitting device having improved luminescence characteristics may be manufactured.
Hereinafter, the structure of the light-emitting device 10 according to an embodiment and a method of manufacturing the light-emitting device 10 will be described with reference to
In
The first electrode 110 may be formed by, for example, depositing or sputtering a material for forming the first electrode 110 on the substrate. In case that the first electrode 110 is an anode, the material for forming the first electrode 110 may be a high work function material that facilitates injection of holes.
The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. In case that the first electrode 110 is a transmissive electrode, the material for forming the first electrode 110 may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), or any combination thereof. In embodiments, in case that the first electrode 110 is a semi-transmissive electrode or a reflective electrode, the material for forming the first electrode 110 may be magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof.
The first electrode 110 may have a single-layered structure consisting of a single layer or a multi-layered structure. For example, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO.
The interlayer 130 may be disposed on the first electrode 110. The interlayer 130 may include an emission layer.
The interlayer 130 may further include a hole transport region arranged between the first electrode 110 and the emission layer and an electron transport region arranged between the emission layer and the second electrode 150.
The interlayer 130 may further include, in addition to various organic materials, a metal-containing compound, such as an organometallic compound, an inorganic material, such as a quantum dot, and the like.
In embodiments, the interlayer 130 may include, two or more emitting units sequentially stacked between the first electrode 110 and the second electrode 150, and a charge generation layer located between the two or more emitting units. In case that the interlayer 130 includes the emitting units and the charge generation layer as described above, the light-emitting device 10 may be a tandem light-emitting device.
The hole transport region may have a single-layered structure consisting of a single layer consisting of a single material, a single-layered structure consisting of a single layer consisting of different materials, or a multi-layered structure including layers which include different materials.
The electron transport region may include the metal oxide layer described above.
The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof.
For example, the hole transport region may have a multi-layered structure including a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, the layers of each structure being stacked sequentially from the first electrode 110.
The hole transport region may include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof:
In Formulae 201 and 202,
For example, each of Formulae 201 and 202 may include at least one of groups represented by Formulae CY201 to CY217:
In Formulae CY201 to CY217, R10b and R10c may each be the same as described herein in connection with R10a, ring CY201 to ring CY204 may each independently be a C3-C20 carbocyclic group or a C1-C20 heterocyclic group, and at least one hydrogen in Formulae CY201 to CY217 may be unsubstituted or substituted with R10a as described herein.
In an embodiment, ring CY201 to ring CY204 in Formulae CY201 to CY217 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.
In embodiments, each of Formulae 201 and 202 may include at least one of groups represented by Formulae CY201 to CY203.
In embodiments, Formula 201 may include at least one of the groups represented by Formulae CY201 to CY203 and at least one of the groups represented by Formulae CY204 to CY217.
In embodiments, in Formula 201, xa1 may be 1, R201 may be a group represented by one of Formulae CY201 to CY203, xa2 may be 0, and R202 may be a group represented by one of Formulae CY204 to CY207.
In embodiments, each of Formulae 201 and 202 may not include a group represented by one of Formulae CY201 to CY203.
In embodiments, each of Formulae 201 and 202 may not include a group represented by one of Formulae CY201 to CY203, and may include at least one of the groups represented by Formulae CY204 to CY217.
In embodiments, each of Formulae 201 and 202 may not include a group represented by one of Formulae CY201 to CY217.
For example, the hole transport region may include one of Compounds HT1 to HT46, m-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, Spiro-TPD, Spiro-NPB, methylated NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), or any combination thereof:
A thickness of the hole transport region may be in a range of about 50 Å to about 10,000 Å. For example, a thickness of the hole transport region may be in a range of about 100 Å to about 4,000 Å. In case that the hole transport region includes a hole injection layer, a hole transport layer, or any combination thereof, a thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å. For example, a thickness of the hole injection layer may be in a range of about 100 Å to about 1,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å. For example, a thickness of the hole transport layer may be in a range of about 100 Å to about 1,500 Å. In case that the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within these ranges, satisfactory hole transporting characteristics may be obtained without a substantial increase in driving voltage.
The emission auxiliary layer may increase light-emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by the emission layer, and the electron blocking layer may block the leakage of electrons from the emission layer to the hole transport region. Materials that may be included in the hole transport region may be included in the emission auxiliary layer and the electron blocking layer.
The hole transport region may further include, in addition to the materials as described above, a charge-generation material for improving conductive properties. The charge-generation material may be uniformly or non-uniformly dispersed in the hole transport region (for example, in the form of a single layer consisting of a charge-generation material).
The charge-generation material may be, for example, a p-dopant.
For example, a lowest unoccupied molecular orbital (LUMO) energy level of the p-dopant may be equal to or less than about −3.5 eV.
In an embodiment, the p-dopant may include a quinone derivative, a cyano group-containing compound, a compound containing element EL1 and element EL2, or any combination thereof.
Examples of the quinone derivative may include TCNQ, F4-TCNQ, and the like.
Examples of the cyano group-containing compound may include HAT-CN and a compound represented by Formula 221:
In Formula 221,
In the compound containing element EL1 and element EL2, element EL1 may be a metal, a metalloid, or any combination thereof, and element EL2 may be a non-metal, a metalloid, or any combination thereof.
Examples of the metal may include: an alkali metal (for example, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc.); an alkaline earth metal (for example, beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), etc.); a transition metal (for example, titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), etc.); a post-transition metal (for example, zinc (Zn), indium (In), tin (Sn), etc.); and a lanthanide metal (for example, lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), etc.).
Examples of the metalloid may include silicon (Si), antimony (Sb), and tellurium (Te).
Examples of the non-metal may include oxygen (O) and halogen (for example, F, CI, Br, I, etc.).
Examples of the compound containing element EL1 and element EL2 may include a metal oxide, a metal halide (for example, a metal fluoride, a metal chloride, a metal bromide, a metal iodide, etc.), a metalloid halide (for example, a metalloid fluoride, a metalloid chloride, a metalloid bromide, a metalloid iodide, etc.), a metal telluride, or any combination thereof.
Examples of the metal oxide may include a tungsten oxide (for example, WO, W2O3, WO2, WO3, W2O5, etc.), a vanadium oxide (for example, VO, V2O3, VO2, V2O5, etc.), a molybdenum oxide (MoO, Mo2O3, MoO2, MoO3, Mo2O5, etc.), and a rhenium oxide (for example, ReO3, etc.).
Examples of the metal halide may include an alkali metal halide, an alkaline earth metal halide, a transition metal halide, a post-transition metal halide, and a lanthanide metal halide.
Examples of the alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, LiI, NaI, KI, RbI, and CsI.
Examples of the alkaline earth metal halide may include BeF2, MgF2, CaF2, SrF2, BaF2, BeCl2, MgCl2, CaCl2, SrCl2, BaCl2, BeBr2, MgBr2, CaBr2, SrBr2, BaBr2, BeI2, MgI2, CaI2, SrI2, and BaI2.
Examples of the transition metal halide may include a titanium halide (for example, TiF4, TiCl4, TiBr4, TiI4, etc.), a zirconium halide (for example, ZrF4, ZrCl4, ZrBr4, ZrI4, etc.), a hafnium halide (for example, HfF4, HfCl4, HfBr4, HfI4, etc.), a vanadium halide (for example, VF3, VCl3, VBr3, VI3, etc.), a niobium halide (for example, NbF3, NbCl3, NbBr3, NbI3, etc.), a tantalum halide (for example, TaF3, TaCl3, TaBr3, TaI3, etc.), a chromium halide (for example, CrF3, CrCl3, CrBr3, CrI3, etc.), a molybdenum halide (for example, MoF3, MoCl3, MoBr3, MoI3, etc.), a tungsten halide (for example, WF3, WCl3, WBr3, WI3, etc.), a manganese halide (for example, MnF2, MnCl2, MnBr2, MnI2, etc.), a technetium halide (for example, TcF2, TcCl2, TcBr2, TcI2, etc.), a rhenium halide (for example, ReF2, ReCl2, ReBr2, ReI2, etc.), an iron halide (for example, FeF2, FeCl2, FeBr2, FeI2, etc.), a ruthenium halide (for example, RuF2, RuCl2, RuBr2, RuI2, etc.), an osmium halide (for example, OsF2, OsCl2, OsBr2, OsI2, etc.), a cobalt halide (for example, CoF2, CoCl2, CoBr2, CoI2, etc.), a rhodium halide (for example, RhF2, RhCl2, RhBr2, RhI2, etc.), an iridium halide (for example, IrF2, IrCl2, IrBr2, IrI2, etc.), a nickel halide (for example, NiF2, NiCl2, NiBr2, NiI2, etc.), a palladium halide (for example, PdF2, PdCl2, PdBr2, PdI2, etc.), a platinum halide (for example, PtF2, PtCl2, PtBr2, PtI2, etc.), a copper halide (for example, CuF, CuCl, CuBr, CuI, etc.), a silver halide (for example, AgF, AgCl, AgBr, AgI, etc.), and a gold halide (for example, AuF, AuCl, AuBr, AuI, etc.).
Examples of the post-transition metal halide may include a zinc halide (for example, ZnF2, ZnCl2, ZnBr2, ZnI2, etc.), an indium halide (for example, InI3, etc.), and a tin halide (for example, SnI2, etc.).
Examples of the lanthanide metal halide may include YbF, YbF2, YbF3, SmF3, YbCl, YbCl2, YbCl3, SmCl3, YbBr, YbBr2, YbBr3, SmBr3, YbI, YbI2, YbI3, and SmI3.
Examples of the metalloid halide may include an antimony halide (for example, SbCl5, etc.).
Examples of the metal telluride may include an alkali metal telluride (for example, Li2Te, Na2Te, K2Te, Rb2Te, Cs2Te, etc.), an alkaline earth metal telluride (for example, BeTe, MgTe, CaTe, SrTe, BaTe, etc.), a transition metal telluride (for example, TiTe2, ZrTe2, HfTe2, V2Te3, Nb2Te3, Ta2Te3, Cr2Te3, Mo2Te3, W2Te3, MnTe, TcTe, ReTe, FeTe, RuTe, OsTe, CoTe, RhTe, IrTe, NiTe, PdTe, PtTe, Cu2Te, CuTe, Ag2Te, AgTe, Au2Te, etc.), a post-transition metal telluride (for example, ZnTe, etc.), and a lanthanide metal telluride (for example, LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, etc.).
In case that the light-emitting device 10 is a full-color light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer, according to a subpixel. At least one of the emission layers may include the quantum dot. For example, the green emission layer may be a quantum dot emission layer including the quantum dot, and the blue emission layer and the red emission layer may each be an organic emission layer including an organic compound.
In embodiments, the emission layer may have a structure in which at least two of a red emission layer, a green emission layer, and a blue emission layer may contact each other or may be separated from each other. At least one emission layer of the at least two emission layers may be a quantum dot emission layer including the quantum dot, and the other emission layer may be an organic emission layer including an organic compound. Other various modifications may be possible.
In embodiments, the emission layer may include a host and a dopant. The dopant may include a phosphorescent dopant, a fluorescent dopant, or any combination thereof.
An amount of the dopant in the emission layer may be in a range of about 0.01 parts by weight to about 15 parts by weight based on 100 parts by weight of the host.
In embodiments, the emission layer may further include a delayed fluorescence material. The delayed fluorescence material may serve as a host or a dopant in the emission layer.
A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å. For example, the thickness of the emission layer may be in a range of about 200 Å to about 600 Å. In case that the thickness of the emission layer is within this range, excellent luminescence characteristics may be obtained without a substantial increase in driving voltage.
The host may include a compound represented by Formula 301:
[Ar301]xb11—[(L301)xb1—R301]xb21 [Formula 301]
In Formula 301,
For example, in case that xb11 in Formula 301 is 2 or more, two or more of Ar301(s) may be linked to each other via a single bond.
In embodiments, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:
In Formulae 301-1 and 301-2,
In embodiments, the host may include an alkali earth metal complex, a post-transition metal complex, or any combination thereof. For example, the host may include a Be complex (for example, Compound H55), an Mg complex, a Zn complex, or any combination thereof.
In embodiments, the host may include one of Compounds H1 to H124, 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), or any combination thereof:
The phosphorescent dopant may include at least one transition metal as a central metal.
The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentadentate ligand, a hexadentate ligand, or any combination thereof.
The phosphorescent dopant may be electrically neutral.
For example, the phosphorescent dopant may include an organometallic compound represented by Formula 401:
In Formulae 401 and 402,
For example, in Formula 402, X401 may be nitrogen, and X402 may be carbon, or each of X401 and X402 may be nitrogen.
In embodiments, in case that xc1 in Formula 401 is 2 or more, two ring A401(s) in two or more of L401(s) may be optionally linked to each other via T402, which is a linking group, or two ring A402(s) may be optionally linked to each other via T403, which is a linking group (see Compounds PD1 to PD4 and PD7). T402 and T403 may each be the same as described herein with respect to T401.
L402 in Formula 401 may be an organic ligand. For example, L402 may include a halogen group, a diketone group (for example, an acetylacetonate group), a carboxylic acid group (for example, a picolinate group), —C(═O), an isonitrile group, —CN group, a phosphorus group (for example, a phosphine group, a phosphite group, etc.), or any combination thereof.
The phosphorescent dopant may include, for example, one of compounds PD1 to PD39, or any combination thereof:
The fluorescent dopant may include an amine group-containing compound, a styryl group-containing compound, or any combination thereof.
For example, the fluorescent dopant may include a compound represented by Formula 501:
In Formula 501,
For example, Ar501 in Formula 501 may be a condensed cyclic group (for example, an anthracene group, a chrysene group, or a pyrene group) in which three or more monocyclic groups are condensed together.
In embodiments, xd4 in Formula 501 may be 2.
For example, the fluorescent dopant may include: one of Compounds FD1 to FD36; DPVBi; DPAVBi; or any combination thereof:
The emission layer may include a delayed fluorescence material.
In the specification, the delayed fluorescence material may be selected from compounds capable of emitting delayed fluorescent light based on a delayed fluorescence emission mechanism.
The delayed fluorescence material included in the emission layer may serve as a host or a dopant depending on the type of other materials included in the emission layer.
In an embodiment, a difference between a triplet energy level (eV) of the delayed fluorescence material and a singlet energy level (eV) of the delayed fluorescence material may be equal to or greater than 0 eV and equal to or less than 0.5 eV. In case that the difference between the triplet energy level (eV) of the delayed fluorescence material and the singlet energy level (eV) of the delayed fluorescence material satisfies the above-described range, up-conversion from the triplet state to the singlet state of the delayed fluorescence materials may effectively occur, and thus, the luminescence efficiency of the light-emitting device 10 may be improved.
For example, the delayed fluorescence material may include a material including at least one electron donor (for example, a π electron-rich C3-C60 cyclic group, such as a carbazole group) and at least one electron acceptor (for example, a sulfoxide group, a cyano group, or a π electron-deficient nitrogen-containing C1-C60 cyclic group), and a material including a C8-C60 polycyclic group in which two or more cyclic groups are condensed while sharing boron (B).
Examples of the delayed fluorescence material may include at least one of Compounds DF1 to DF9:
The electron transport region may have a single-layered structure consisting of a single layer consisting of a single material, a single-layered structure consisting of a single layer consisting of different materials, or a multi-layered structure including layers which include different materials.
The electron transport region may include the metal oxide layer described above.
The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, an electron injection layer, or any combination thereof, and at least one selected from the buffer layer, the hole blocking layer, the electron transport layer, and the electron injection layer may include the metal oxide layer.
For example, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, the constituting layers of each structure being sequentially stacked from the emission layer, and each structure may include the metal oxide layer.
The electron transport region may further include a metal oxide, in addition to the metal oxide particle included in the metal oxide layer described above, and the metal of the metal oxide may include Zn, Ti, Zr, Sn, W, Ta, Ni, Mo, Cu, Mg, Co, Mn, Y, Al, or any combination thereof. The electron transport region may further include a metal sulfide, in addition to the metal oxide particle included in the metal oxide layer described above, and for example, may include CuSCN or the like.
The electron transport region (for example, the electron injection layer or the electron transport layer in electron transport region) may further include, in addition to the metal oxide particle included in the metal oxide layer described above, a metal oxide represented by Formula 2-1:
M1pM21-pOq [Formula 2-1]
In Formula 2-1,
In embodiments, the metal oxide may be represented by Formula 2-2:
Zn(1-r)MrO [Formula 2-2]
In Formula 2-2,
In an embodiment, the electron transport region may include ZnO or ZnMgO.
In embodiments, the electron transport region may further include, for example, ZnO, TiO2, WO3, SnO2, In2O3, Nb2O5, Fe2O3, CeO2, SrTiO3, Zn2SnO4, BaSnO3, In253, ZnSiO, PC60BM, PC70BM, Mg-doped ZnO (ZnMgO), Al-doped ZnO (AZO), Ga-doped ZnO (GZO), In-doped ZnO (IZO), Al-doped TiO2, Ga-doped TiO2, In-doped TiO2, Al-doped WO3, Ga-doped WO3, In-doped WO3, Al-doped SnO2, Ga-doped SnO2, In-doped SnO2, Mg-doped In2O3, Al-doped In2O3, Ga-doped In2O3, Mg-doped Nb2O5, Al-doped Nb2O5, Ga-doped Nb2O5, Mg-doped Fe2O3, Al-doped Fe2O3, Ga-doped Fe2O3, In-doped Fe2O3, Mg-doped CeO2, Al-doped CeO2, Ga-doped CeO2, In-doped CeO2, Mg-doped SrTiO3, Al-doped SrTiO3, Ga-doped SrTiO3, In-doped SrTiO3, Mg-doped Zn2SnO4, Al-doped Zn2SnO4, Ga-doped Zn2SnO4, In-doped Zn2SnO4, Mg-doped BaSnO3, Al-doped BaSnO3, Ga-doped BaSnO3, In-doped BaSnO3, Mg-doped In2S3, Al-doped In2S3, Ga-doped In2S3, In-doped In2S3, Mg-doped ZnSiO, Al-doped ZnSiO, Ga-doped ZnSiO, In-doped ZnSiO, or any combination thereof, in addition to the metal oxide layer formed using the metal oxide composition described above.
The electron transport region (for example, the buffer layer, the hole blocking layer, the electron control layer, or the electron transport layer in the electron transport region) may further include, in addition to the metal oxide particle included in the metal oxide layer described above, a metal-free compound including at least one π electron-deficient nitrogen-containing C1-C60 cyclic group.
For example, the electron transport region may further include, in addition to the metal oxide particle included in the metal oxide layer described above, a compound represented by Formula 601:
[Ar601]xe11—[(L601)xe1—R601]xe21 [Formula 601]
In Formula 601,
In an embodiment in Formula 601, when xe11 is 2 or more, two or more of Ar601(s) may be linked to each other via a single bond.
In embodiments, Ar601 in Formula 601 may be a substituted or unsubstituted anthracene group.
In embodiments, the electron transport region may further include, in addition to the metal oxide particle included in the metal oxide layer described above, a compound represented by Formula 601-1:
In Formula 601-1,
In an embodiment, in Formulae 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.
The electron transport region may further include, in addition to the metal oxide particle included in the metal oxide layer described above, one of Compounds ET1 to ET45, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq3, BAlq, TAZ, NTAZ, or any combination thereof:
A thickness of the electron transport region may be in a range of about 100 Å to about 5,000 Å. For example, a thickness of the electron transport region may be in a range of about 160 Å to about 4,000 Å. In case that the electron transport region includes a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or any combination thereof, a thickness of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 20 Å to about 1,000 Å and a thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, For example, a thickness of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 30 Å to about 300 Å and a thickness of the electron transport layer may be in a range of about 150 Å to about 500 Å. In case that the thicknesses of the buffer layer, the hole blocking layer, the electron control layer, the electron transport layer, and/or the electron transport region are within these ranges, satisfactory electron transporting characteristics may be obtained without a substantial increase in driving voltage.
The electron transport region may include the electron transport layer, and the electron transport layer may include the metal oxide layer described above.
The electron transport layer in the electron transport region may further include a metal-containing material, in addition to the metal oxide particle included in the metal oxide layer.
The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of the alkali metal complex may be a Li ion, a Na ion, a K ion, a Rb ion, or a Cs ion, and a metal ion of the alkaline earth metal complex may be a Be ion, a Mg ion, a Ca ion, a Sr ion, or a Ba ion. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may include hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.
For example, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (LiQ) or ET-D2:
The electron transport region may include an electron injection layer that facilitates the injection of electrons from the second electrode 150. The electron injection layer may be in direct contact with the second electrode 150.
The electron injection layer may have a single-layered structure consisting of a single layer consisting of a single material, a single-layered structure consisting of a single layer consisting of different materials, or a multi-layered structure including layers which include different materials.
The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof.
The alkali metal may include Li, Na, K, Rb, Cs, or any combination thereof. The alkaline earth metal may include Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may include Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.
The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may be oxides, halides (for example, fluorides, chlorides, bromides, or iodides), or tellurides of the alkali metal, the alkaline earth metal, and the rare earth metal; or any combination thereof.
The alkali metal-containing compound may include alkali metal oxides, such as Li2O, Cs2O, or K2O; alkali metal halides, such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or KI; or any combination thereof. The alkaline earth metal-containing compound may include an alkaline earth metal compound, such as BaO, SrO, CaO, BaxSr1-xO (wherein x is a real number satisfying the condition of 0<x<1), or BaxCa1-xO (wherein x is a real number satisfying the condition of 0<x<1). The rare earth metal-containing compound may include YbF3, ScF3, Sc2O3, Y2O3, Ce2O3, GdF3, TbF3, YbI3, ScI3, TbI3, or any combination thereof. In embodiments, the rare earth metal-containing compound may include lanthanide metal telluride. Examples of the lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La2Te3, Ce2Te3, Pr2Te3, Nd2Te3, Pm2Te3, Sm2Te3, Eu2Te3, Gd2Te3, Tb2Te3, Dy2Te3, Ho2Te3, Er2Te3, Tm2Te3, Yb2Te3, and Lu2Te3.
The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include one of ions of the alkali metal, the alkaline earth metal, and the rare earth metal and a ligand linked to the metal ion (for example, hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenyl benzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof).
The electron injection layer may consist of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In embodiments, the electron injection layer may further include an organic material (for example, a compound represented by Formula 601).
In embodiments, the electron injection layer may consist of an alkali metal-containing compound (for example, an alkali metal halide); or a) an alkali metal-containing compound (for example, an alkali metal halide), and b) an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. For example, the electron injection layer may be a KI:Yb co-deposited layer, an RbI:Yb co-deposited layer, a LiF:Yb co-deposited layer, or the like.
In case that the electron injection layer further includes an organic material, an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth-metal complex, a rare earth metal complex, or any combination thereof may be uniformly or non-uniformly dispersed in a matrix including the organic material.
A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å. In an embodiment, a thickness of the electron injection layer may be in a range of about 3 Å to about 90 Å. In case that the thickness of the electron injection layer is within this range, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.
The second electrode 150 may be disposed on the interlayer 130 as described above. The second electrode 150 may be a cathode, which is an electron injection electrode, and a material for forming the second electrode 150 may include a metal, an alloy, an electrically conductive compound, or any combination thereof, each having a low-work function.
The second electrode 150 may include lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ytterbium (Yb), silver-ytterbium (Ag—Yb), ITO, IZO, or any combination thereof. The second electrode 150 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.
The second electrode 150 may have a single-layered structure or a multi-layered structure.
A first capping layer may be arranged outside the first electrode 110, and/or a second capping layer may be arranged outside the second electrode 150. The light-emitting device 10 may have a structure in which the first capping layer, the first electrode 110, the interlayer 130, and the second electrode 150 are sequentially stacked in the stated order, a structure in which the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are sequentially stacked in the stated order, or a structure in which the first capping layer, the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are sequentially stacked in the stated order.
Light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the first electrode 110, which is a semi-transmissive electrode or a transmissive electrode, and the first capping layer. Light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the second electrode 150, which is a semi-transmissive electrode or a transmissive electrode, and the second capping layer.
The first capping layer and the second capping layer may increase external luminescence efficiency according to the principle of constructive interference. Accordingly, the light extraction efficiency of the light-emitting device 10 may be increased, so that the luminescence efficiency of the light-emitting device 10 may be improved.
Each of the first capping layer and the second capping layer may include a material having a refractive index equal to or greater than about 1.6 or more (at 589 nm).
The first capping layer and the second capping layer may each independently be an organic capping layer including an organic material, an inorganic capping layer including an inorganic material, or an organic-inorganic composite capping layer including an organic material and an inorganic material.
At least one of the first capping layer and the second capping layer may each independently include a carbocyclic compound, a heterocyclic compound, an amine group-containing compound, a porphine derivative, a phthalocyanine derivative, a naphthalocyanine derivative, an alkali metal complex, an alkaline earth metal complex, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may optionally be substituted with a substituent including O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In an embodiment, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.
For example, at least one of the first capping layer and the second capping layer may each independently include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof.
In embodiments, at least one of the first capping layer and the second capping layer may each independently include one of Compounds HT28 to HT33, one of Compounds CP1 to CP6, β-NPB, or any combination thereof:
The film may be, for example, an optical member (or, a light-controlling member) (for example, a color filter, a color-conversion member, a capping layer, a light extraction efficiency improvement layer, a selective light-absorbing layer, a polarizing layer, a quantum dot-containing layer, etc.), a light-blocking member (for example, a light reflection layer, a light-absorbing layer, etc.), or a protection member (for example, an insulating layer, a dielectric material layer, etc.).
The light-emitting device may be included in various electronic apparatuses. For example, the electronic apparatus including the light-emitting device may be a light-emitting apparatus, an authentication apparatus, or the like.
The electronic apparatus (for example, a light-emitting apparatus) may further include, in addition to the light-emitting device, a color filter, a color conversion layer, or a color filter and a color conversion layer. The color filter and/or the color conversion layer may be arranged in at least one direction in which light emitted from the light-emitting device travels. For example, the light emitted from the light-emitting device may be blue light or white light. Details for the light-emitting device may be the same as described herein. In an embodiment, the color conversion layer may include a quantum dot. The quantum dot may be, for example, a quantum dot as described herein.
The electronic apparatus may include a first substrate. The first substrate may include subpixel areas, the color filter may include color filter areas respectively corresponding to the subpixel areas, and the color conversion layer may include color conversion areas respectively corresponding to the subpixel areas.
A pixel defining film may be arranged among the subpixel areas to define each of the subpixel areas.
The color filter may further include color filter areas and light-shielding patterns arranged among the color filter areas, and the color conversion layer may further include color conversion areas and light-shielding patterns arranged among the color conversion areas.
The color filter areas (or the color conversion areas) may include a first area emitting a first color light, a second area emitting a second color light, and/or a third area emitting a third color light, and the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths. For example, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. For example, the color filter areas (or the color conversion areas) may include quantum dots. In detail, the first area may include a red quantum dot, the second area may include a green quantum dot, and the third area may not include a quantum dot. Details on the quantum dots may be the same as described herein. The first area, the second area, and/or the third area may each further include a scatterer.
For example, the light-emitting device may emit a first light, the first area may absorb the first light to emit a first-first color light, the second area may absorb the first light to emit a second-first color light, and the third area may absorb the first light to emit a third-first color light. In this regard, the first-first color light, the second-first color light, and the third-first color light may have different maximum emission wavelengths. In detail, the first light may be blue light, the first-first color light may be red light, the second-first color light may be green light, and the third-first color light may be blue light.
The electronic apparatus may further include a thin-film transistor, in addition to the light-emitting device as described above. The thin-film transistor may include a source electrode, a drain electrode, and an activation layer, and any one of the source electrode and the drain electrode may be electrically connected to any one of the first electrode and the second electrode of the light-emitting device.
The thin-film transistor may further include a gate electrode, a gate insulating film, and the like.
The activation layer may include a crystalline silicon, an amorphous silicon, an organic semiconductor, an oxide semiconductor, and the like.
The electronic apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion may be arranged between the color filter and/or the color conversion layer and the light-emitting device. The sealing portion allows light from the light-emitting device to be extracted to the outside, and simultaneously prevents ambient air and moisture from penetrating into the light-emitting device. The sealing portion may be a sealing substrate including a transparent glass substrate or a plastic substrate. The sealing portion may be a thin-film encapsulation layer including at least one layer of an organic layer and/or an inorganic layer. In case that the sealing portion is a thin-film encapsulating layer, the electronic apparatus may be flexible.
Various functional layers may be additionally disposed on the sealing portion, in addition to the color filter and/or the color conversion layer, according to the use of the electronic apparatus. Examples of the functional layer may include a touch screen layer, a polarizing layer, and the like. The touch screen layer may be a pressure-sensitive touch screen layer, a capacitive touch screen layer, or an infrared touch screen layer. The authentication apparatus may be, for example, a biometric authentication apparatus that authenticates an individual by using biometric information of a living body (for example, fingertips, pupils, etc.).
The authentication apparatus may further include, in addition to the light-emitting device as described above, a biometric information collector.
The electronic apparatus may be applied to various displays, light sources, lighting, personal computers (for example, a mobile personal computer), mobile phones, digital cameras, electronic organizers, electronic dictionaries, electronic game machines, medical instruments (for example, electronic thermometers, sphygmomanometers, blood glucose meters, pulse measurement devices, pulse wave measurement devices, electrocardiogram displays, ultrasonic diagnostic devices, or endoscope displays), fish finders, various measuring instruments, meters (for example, meters for a vehicle, an aircraft, and a vessel), projectors, and the like.
The electronic apparatus 180 of
The substrate 100 may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer 210 may be disposed on the substrate 100. The buffer layer 210 may prevent penetration of impurities through the substrate 100 and may provide a flat surface on the substrate 100.
The TFT 200 may be disposed on the buffer layer 210. The TFT 200 may include an activation layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.
The activation layer 220 may include an inorganic semiconductor, such as silicon or polysilicon, an organic semiconductor, or an oxide semiconductor, and may include a source region, a drain region, and a channel region.
A gate insulating film 230 for insulating the activation layer 220 from the gate electrode 240 may be disposed on the activation layer 220, and the gate electrode 240 may be disposed on the gate insulating film 230.
An interlayer insulating film 250 may be disposed on the gate electrode 240. The interlayer insulating film 250 may be arranged between the gate electrode 240 and the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to provide insulation therebetween.
The source electrode 260 and the drain electrode 270 may be disposed on the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose the source region and the drain region of the activation layer 220, and the source electrode 260 and the drain electrode 270 may be arranged to contact the exposed portions of the source region and the drain region of the activation layer 220.
The TFT 200 may be electrically connected to a light-emitting device to drive the light-emitting device, and may be covered by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or any combination thereof. A light-emitting device may be provided on the passivation layer 280. The light-emitting device may include a first electrode 110, an interlayer 130, and a second electrode 150.
The first electrode 110 may be disposed on the passivation layer 280. The passivation layer 280 may be arranged to expose a portion of the drain electrode 270, not fully covering the drain electrode 270, and the first electrode 110 may be arranged to be connected to the exposed portion of the drain electrode 270.
A pixel defining layer 290 including an insulating material may be disposed on the first electrode 110. The pixel defining layer 290 may expose a portion of the first electrode 110, and the interlayer 130 may be formed in the exposed portion of the first electrode 110. The pixel defining layer 290 may be a polyimide or polyacrylic organic film. Although not shown in
The second electrode 150 may be disposed on the interlayer 130, and a capping layer 170 may be additionally formed on the second electrode 150. The capping layer 170 may be formed to cover the second electrode 150.
The encapsulation portion 300 may be disposed on the capping layer 170. The encapsulation portion 300 may be disposed on a light-emitting device to protect the light-emitting device from moisture or oxygen. The encapsulation portion 300 may include: an inorganic film including silicon nitride (SiNx), silicon oxide (SiOx), indium tin oxide, indium zinc oxide, or any combination thereof; an organic film including polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxy methylene, polyarylate, hexamethyl disiloxane, an acrylic resin (for example, polymethyl methacrylate, polyacrylic acid, etc.), an epoxy resin (for example, aliphatic glycidyl ether (AGE), etc.), or any combination thereof; or a combination of the inorganic film and the organic film.
The electronic apparatus 190 of
Respective layers included in the hole transport region, the emission layer, and respective layers included in the electron transport region may be formed in a certain region by using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, laser-induced thermal imaging, and the like.
In case that respective layers included in the hole transport region, the emission layer, and respective layers included in the electron transport region are formed by vacuum deposition, the deposition may be performed at a deposition temperature of about 100° C. to about 500° C., a vacuum degree of about 10−8 torr to about 10−3 torr, and a deposition speed of about 0.01 Å/sec to about 100 Å/sec, depending on a material to be included in a layer to be formed and the structure of a layer to be formed.
The term “C3-C60 carbocyclic group” as used herein may be a cyclic group consisting of carbon only as a ring-forming atom and having 3 to 60 carbon atoms, and the term “C1-C60 heterocyclic group” as used herein may be a cyclic group that has 1 to 60 carbon atoms and further has, in addition to carbon, a heteroatom as a ring-forming atom. The C3-C60 carbocyclic group and the C1-C60 heterocyclic group may each be a monocyclic group consisting of one ring or a polycyclic group in which two or more rings are condensed with each other. For example, the C1-C60 heterocyclic group may have 3 to 61 ring-forming atoms.
The term “cyclic group” as used herein may include both the C3-C60 carbocyclic group and the C1-C60 heterocyclic group.
The term “π electron-rich C3-C60 cyclic group” as used herein may be a cyclic group that has 3 to 60 carbon atoms and does not include *—N═*′ as a ring-forming moiety. The term “π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein may be a heterocyclic group that has 1 to 60 carbon atoms and includes *—N═*′ as a ring-forming moiety.
For example,
The terms “cyclic group”, “C3-C60 carbocyclic group”, “C1-C60 heterocyclic group”, “π electron-rich C3-C60 cyclic group”, or “π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein may each be a group condensed to any cyclic group, a monovalent group, or a polyvalent group (for example, a divalent group, a trivalent group, a tetravalent group, etc.) according to the structure of a formula for which the corresponding term is used. For example, a “benzene group” may be a benzo group, a phenyl group, a phenylene group, or the like, which may be readily understood by one of ordinary skill in the art according to the structure of a formula including the “benzene group.”
Examples of the monovalent C3-C60 carbocyclic group and the monovalent C1-C60 heterocyclic group may include a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, and examples of the divalent C3-C60 carbocyclic group and the divalent C1-C60 heterocyclic group may include a C3-C10 cycloalkylene group, a C1-C10 heterocycloalkylene group, a C3-C10 cycloalkenylene group, a C1-C10 heterocycloalkenylene group, a C6-C60 arylene group, a C1-C60 heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a substituted or unsubstituted divalent non-aromatic condensed heteropolycyclic group.
The term “C1-C60 alkyl group” as used herein may be a linear or branched aliphatic hydrocarbon monovalent group that has 1 to 60 carbon atoms, and examples thereof may include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl group, a sec-decyl group, and a tert-decyl group. The term “C1-C60 alkylene group” as used herein may be a divalent group having a same structure as the C1-C60 alkyl group.
The term “C2-C60 alkenyl group” as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon double bond in the middle or at a terminus of the C2-C60 alkyl group, and examples thereof may include an ethenyl group, a propenyl group, and a butenyl group. The term “C2-C60 alkenylene group” as used herein may be a divalent group having a same structure as the C2-C60 alkenyl group.
The term “C2-C60 alkynyl group” as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof may include an ethynyl group and a propynyl group. The term “C2-C60 alkynylene group” as used herein may be a divalent group having a same structure as the C2-C60 alkynyl group.
The term “C1-C60 alkoxy group” as used herein may be a monovalent group represented by —O(A101) (wherein Aioi may be the C1-C60 alkyl group), and examples thereof may include a methoxy group, an ethoxy group, and an isopropyloxy group.
The term “C3-C10 cycloalkyl group” as used herein may be a monovalent saturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and examples thereof may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group (or bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, and a bicyclo[2.2.2]octyl group. The term “C3-C10 cycloalkylene group” as used herein may be a divalent group having a same structure as the C3-C10 cycloalkyl group.
The term “C1-C10 heterocycloalkyl group” as used herein may be a monovalent cyclic group of 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms, and examples may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C1-C10 heterocycloalkylene group” as used herein may be a divalent group having a same structure as the C1-C10 heterocycloalkyl group.
The term “C3-C10 cycloalkenyl group” as used herein may be a monovalent cyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and examples thereof may include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C3-C10 cycloalkenylene group” as used herein may be a divalent group having a same structure as the C3-C10 cycloalkenyl group.
The term “C1-C10 heterocycloalkenyl group” as used herein may be a monovalent cyclic group of 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms, and having at least one carbon-carbon double bond (or at least one double bond) in the cyclic structure thereof. Examples of the C1-C10 heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C1-C10 heterocycloalkenylene group” as used herein may be a divalent group having a same structure as the C1-C10 heterocycloalkenyl group.
The term “C6-C60 aryl group” as used herein may be a monovalent group having a carbocyclic aromatic system of 6 to 60 carbon atoms, and the term “C6-C60 arylene group” as used herein may be a divalent group having a carbocyclic aromatic system of 6 to 60 carbon atoms. Examples of the C6-C60 aryl group may include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, and an ovalenyl group. In case that the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the rings may be condensed with each other.
The term “C1-C60 heteroaryl group” as used herein may be a monovalent group having a heterocyclic aromatic system of 1 to 60 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms. The term “C1-C60 heteroarylene group” as used herein may be a divalent group having a heterocyclic aromatic system of 1 to 60 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms. Examples of the C1-C60 heteroaryl group may include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, and a naphthyridinyl group. In case that the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the rings may be condensed with each other.
The term “monovalent non-aromatic condensed polycyclic group” as used herein may be a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed to each other, only carbon atoms as ring-forming atoms, and no aromaticity in its entire molecular structure. Examples of the monovalent non-aromatic condensed polycyclic group may include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, and an indenoanthracenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein may be a divalent group having a same structure as the monovalent non-aromatic condensed polycyclic group.
The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein may be a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed to each other, further including, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms, and having non-aromaticity in its entire molecular structure. Examples of the monovalent non-aromatic condensed heteropolycyclic group may include a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzoxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indeno carbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphtho silolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein may be a divalent group having a same structure as the monovalent non-aromatic condensed heteropolycyclic group.
The term “C6-C60 aryloxy group” as used herein may be —O(A102) (wherein A102 may be the C6-C60 aryl group), and the term “C6-C60 arylthio group” as used herein may be —S(A103) (wherein A103 is the C6-C60 aryl group).
The term “C7-C60 arylalkyl group” as used herein may be —(A104)(A105) (wherein A104 may be a C1-C54 alkylene group, and A105 may be a C6-C59 aryl group), and the term “C2-C60 heteroarylalkyl group” as used herein may be —(A106)(A107) (wherein A106 may be a C1-C59 alkylene group, and A107 may be a C1-C59 heteroaryl group).
The term “R10a” as used herein may be:
Q1, Q11 to Q13, Q21 to Q23 and Q31 to Q33 as used herein may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C1-C60 alkyl group; a C2-C60 alkenyl group; a C2-C60 alkynyl group; a C1-C60 alkoxy group; a C3-C60 carbocyclic group or a C1-C60 heterocyclic group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C1-C60 alkyl group, a C1-C60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof; a C7-C60 arylalkyl group; or a C2-C60 heteroarylalkyl group.
The term “heteroatom” as used herein may be any atom other than a carbon atom or a hydrogen atom. Examples of the heteroatom may include O, S, N, P, Si, B, Ge, Se, or any combination thereof.
The term “third-row transition metal” as used herein may include hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), and gold (Au).
The term “Ph” as used herein refers to a phenyl group, the term “Me” as used herein refers to a methyl group, the term “Et” as used herein refers to an ethyl group, the terms “tert-Bu” or “But” as used herein each refer to a tert-butyl group, and the term “OMe” as used herein refers to a methoxy group.
The term “biphenyl group” as used herein may be “a phenyl group substituted with a phenyl group.” For example, the “biphenyl group” may be a substituted phenyl group having a C6-C60 aryl group as a substituent.
The term “terphenyl group” as used herein may be “a phenyl group substituted with a biphenyl group”. For example, the “terphenyl group” may be a substituted phenyl group having, as a substituent, a C6-C60 aryl group substituted with a C6-C60 aryl group.
The symbols * and *′ as used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula or moiety.
Hereinafter, a compound according to embodiments and a light-emitting device according to embodiments will be described in detail with reference to Synthesis Examples and Examples. The wording “B was used instead of A” used in describing Synthesis Examples means that an identical molar equivalent of B was used in place of A.
After 4 mmol of zinc acetate dihydrate as a metal oxide precursor was dissolved in 30 ml of DMSO as a solvent, a solution in which 5 mmol of TMAH as an oxidizing agent was dissolved in 10 ml of ethanol (EtOH) was slowly added dropwise thereto, and the mixture was stirred for 1 hour to obtain ZnO dispersed in EtOH.
0.8 part by weight of ZnCl2 was added to ZnO dispersed in EtOH, and the mixture was stirred at 30° C. for 12 hours.
Metal oxide compositions according to Preparation Examples 2 to 4 and Comparative Preparation Examples 1 to 6 were prepared in the same manner as in Preparation Example 1, except that the type of metal oxide precursor, the type of first metal oxide particle, the type of halide compound, and the treatment temperature (whether heating was performed or not) were changed as shown in Table 1.
The average particle diameter (D50) of each of metal oxide particles included in the compositions according to Preparation Examples 1 to 4 and Comparative Preparation Examples 1 to 6 was measured. The average particle diameter (D50) was measured using DLS equipment (Nano-ZS90 manufactured by Malvern Inc.). The measurement results are shown in Table 2.
As an anode, a glass substrate (product of Corning Inc.) with a 15 Ω/cm2 (1,200 Å) ITO electrode formed thereon was cut to a size of 50 mm×50 mm×0.5 mm, sonicated using isopropyl alcohol and pure water each for 5 minutes, and cleaned by irradiation of ultraviolet rays and exposure of ozone thereto for 30 minutes. The glass substrate was mounted on a vacuum deposition apparatus.
PEDOT:PSS (Clevios™ HIL8) was spin-coated on the anode to form a film having a thickness of 60 nm, and a baking process was performed thereon at 120° C. for 10 minutes to form a hole injection layer. Compound 101 was spin-coated on the hole injection layer to form a film having a thickness of 20 nm, and a baking process was performed thereon at 120° C. for 10 minutes to form a hole transport layer.
Red InP quantum dots dispersed in octane were spin-coated on the hole transport layer to form a film having a thickness of 20 nm, and a baking process was performed thereon at 100° C. for 10 minutes to form a red emission layer. The metal oxide composition according to Preparation Example 1 was spin-coated on the red emission layer to form a film having a thickness of 30 nm, and a baking process was performed thereon at 120° C. for 10 minutes to form an electron transport layer.
Al was deposited on the electron transport layer to form a cathode having a thickness of a 100 nm, thereby completing the manufacture of a light-emitting device. For the deposition, a Suicel plus 200 evaporator from Sunic Systems Inc. was used.
Light-emitting devices according to Examples 2 to 4 and Comparative Examples 1 to 6 were manufactured in the same manner as in Example 1, except that the type of metal oxide composition was changed as shown in Table 2.
The driving voltage, efficiency, color coordinates, and lifespan (T90) of the light-emitting devices according to Examples 1 to 4 and Comparative Examples 1 to 6 were measured using a current-voltmeter (Kethley SMU 236) and a luminance meter PR650. The measurement results are shown in Table 3.
The lifespan (T90) indicates the time (hr) it takes for the luminance to reach 90% when the initial luminance (at 10 mA/cm2) is 100%.
Referring to Tables 2 and 3, the light-emitting devices of Examples 1 to 4, in which a metal oxide particle was treated with a halide compound at a temperature of 60° C. or less, were found to have improved driving voltage, efficiency, and lifespan, as compared with the light-emitting devices of Comparative Examples 1 and 2, in which a metal oxide particle was not treated with a halide compound.
The light-emitting devices of Examples 1 to 4, in which a metal oxide particle was treated with a halide compound at a temperature of 60° C. or less, were found to have improved driving voltage, efficiency, and lifespan, as compared with the light-emitting devices of Comparative Examples 3 to 6, in which a metal oxide particle was treated with a halide compound at a temperature exceeding 60° C.
According to embodiments, due to the addition of and treatment with a halide compound in preparing a metal oxide composition, electron transport and electron injection characteristics of a metal oxide particle may be improved, thereby enabling the manufacture of a light-emitting device having improved luminescence characteristics.
Embodiments have been disclosed herein, and although terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. In some instances, as would be apparent to one of ordinary skill in the art, features, characteristics, and/or elements described in connection with an embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the disclosure as set forth in the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0041905 | Apr 2022 | KR | national |
