Patent Application
20250197719
This application claims priority to and benefits of Korean Patent Application No. 10-2023-0183479 under 35 U.S.C. § 119, filed on Dec. 15, 2023, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.
Embodiments relate to a composition, a light-emitting device using the composition, and an electronic apparatus including the light-emitting device.
Light-emitting devices are self-emissive devices that have a wide viewing angle, a high contrast ratio, and a short response time, and show excellent characteristics in terms of luminance, driving voltage, and response speed.
In a light-emitting device, a first electrode may be located on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode may be sequentially formed on the first electrode. Holes injected from the first electrode move to the emission layer through a non-luminescent exciton transport region that does not contribute to light emission among excitons generated inside the emission layer, and electrons injected from the second electrode pass through the electron transport region to the emission layer. Carriers, such as holes and electrons, recombine in the emission layer to produce excitons. The excitons may transition from an excited state to a ground state, thus 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 composition that includes a nanomaterial, a light-emitting device using the composition, 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.
According to embodiments, a composition may include a nanomaterial and a solvent, wherein the nanomaterial may include a metal oxide and a ligand on a surface of the metal oxide, and the ligand may include a group represented by Formula 1:
In Formula 1,
In an embodiment, a1 may be 1 or 2.
In an embodiment, R1 may be a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C3-C10 cycloalkyl group unsubstituted or substituted with at least one R10a, or a C6-C60 aryl group unsubstituted or substituted with at least one R10a.
In an embodiment, R1 may be a C1-C20 alkyl group, a C2-C20 alkenyl group, a C3-C10 cycloalkyl group, or a C6-C20 aryl group, each unsubstituted or substituted with deuterium, a C1-C1 alkyl group, a C2-C10 alkenyl group, a phenyl group, or any combination thereof.
In an embodiment, R11 and R12 may each independently be hydrogen, deuterium, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or a C2-C10 alkenyl group.
In an embodiment, L1 may be *—C(R11)(R12)—*; a1 may be 1 or 2; and R11 and R12 may each independently be hydrogen, deuterium, or a C1-C5 alkyl group.
In an embodiment, the ligand may include a group represented by one of Formulae 1A to 1F, which are explained below.
In an embodiment, a concentration of the ligand in the composition may be less than 20 wt %, based on 100 wt % of the metal oxide nanoparticles.
In an embodiment, a concentration of the ligand in the composition may be in a range of about 0.1 wt % to about 15 wt %, based on 100 wt % of the metal oxide nanoparticles.
In an embodiment, the metal oxide may include Zn, Ti, Zr, Sn, W, Ta, Ni, Mo, Cu, Mg, Co, Mn, Y, Al, Fe, Ge, Pb, Cr, or any combination thereof.
In an embodiment, the metal oxide may be represented by Formula 2, which is explained below.
In an embodiment, the metal oxide may be represented by Formula 2-1, which is explained below.
According to embodiments, a light-emitting device 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 by using the composition described herein.
In an embodiment, the emission layer may include quantum dots.
In an embodiment, the first electrode may be an anode; the second electrode may be a cathode; the interlayer 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; 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; and the electron transport region may include a hole-blocking layer, an electron transport layer, an electron injection layer, an electron control layer, or any combination thereof.
In an embodiment, the hole transport region or the electron transport region may include the metal oxide layer.
In an embodiment, the electron transport layer or the electron injection layer may include the metal oxide layer.
According to embodiments, an electronic apparatus may include the light-emitting device.
In an embodiment, the electronic apparatus may further include a thin-film transistor, wherein the thin-film transistor may include a source electrode and a drain electrode, and the first electrode of the light-emitting device may be electrically connected to at least one of the source electrode and the drain electrode.
In an embodiment, the electronic apparatus may further include a color filter, a color conversion layer, a touch screen layer, a polarizing layer, or a combination thereof.
It is to be understood that the embodiments above are described in a generic and explanatory sense only and not for the purposes of limitation, and the disclosure is not limited to the embodiments described above.
The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification.
The drawings illustrate embodiments of the disclosure and principles thereof. The above and other aspects and features of the disclosure will become 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 reference numbers and reference characters refer to like elements throughout.
In the specification, 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 specification, 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.
In the specification, 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.
In the specification, 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 consisting of” for the purpose of its meaning and interpretation. For example, “at least one of A, B, and C” may be understood to mean A only, B only, C only, or any combination of two or more of A, B, and C, such as ABC, ACC, BC, or CC. 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 Tl, 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 in 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 metalloid such as Si. Examples of the metalloid may include B, Si, Ge, As, Sb, Te, and the like.
Hereinafter, a composition according to an embodiment is described.
According to embodiments, a composition may include: a nanomaterial; and a solvent, wherein
the nanomaterial may include: a metal oxide; and a ligand on a surface of the metal oxide.
According to embodiments, the ligand may include a group represented by Formula 1:
In Formula 1, L1 may be *—C(R11)(R12)—*′ or *—C(R11)═C(R12)—*′, and * and *′ each indicate a binding site to a neighboring atom.
In Formula 1, a1 may be an integer from 1 to 5, wherein when a1 is 2 or more, two or more L1 may be identical to or different from each other.
In an embodiment, a1 may be 1 or 2.
In Formula 1, L2 may be *—O—*′ or *—C(═O)—*′, and * and *′ each indicate a binding site to a neighboring atom.
In Formula 1, a2 may be 0 or 1, wherein when a2 is 0, L2 may not be present.
In Formula 1, R1 may be a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkynyl group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, or a C1-C6a heterocyclic group unsubstituted or substituted with at least one R10a.
In an embodiment, R1 may be a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C3-C1 cycloalkyl group unsubstituted or substituted with at least one R10a, or a C6-C60 aryl group unsubstituted or substituted with at least one R10a.
In an embodiment, R1 may be a C1-C20 alkyl group, a C2-C20 alkenyl group, a C3-C1 cycloalkyl group, or a C6-C20 aryl group, each unsubstituted or substituted with deuterium, a C1-C10 alkyl group, a C2-C10 alkenyl group, a phenyl group, or any combination thereof.
For example, R1 may be a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an ethylene group, a propylene group, a 2-methylpropylene group, a butylene group, or a 2-methylbutylene group.
In Formula 1, R11 and R12 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkynyl group unsubstituted or substituted with at least one R10a, a C1-C60 alkoxy group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, a C6-C60 aryloxy group unsubstituted or substituted with at least one R10a, a C6-C60 arylthio group unsubstituted or substituted with at least one R10a, —C(Q1)(Q2)(Q3), —Si(Q1)(Q2)(Q3), —N(Q1)(Q2), —B(Q1)(Q2), —C(═O)(Q1), —S(═O)2(Q1), or —P(═O)(Q1)(Q2).
In an embodiment, R11 and R12 may each independently be:
In an embodiment, R11 and R12 may each independently be hydrogen, deuterium, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or a C2-C10 alkenyl group.
In Formula 1, * indicates a binding site to a surface of a metal oxide.
In an embodiment, in Formula 1, L1 may be *—C(R11)(R12)—*; a1 may be 1 or 2; and R11 and R12 may each independently be hydrogen, deuterium, or a C1-C5 alkyl group.
In an embodiment, the ligand may include a group represented by any one of Formulae 1A to 1F:
In Formulae 1A to 1F, * indicates a binding site to a surface of a metal oxide.
In an embodiment, the metal oxide may include Zn, Ti, Zr, Sn, W, Ta, Ni, Mo, Cu, Mg, Co, Mn, Y, Al, Fe, Ge, Pb, Cr, or any combination thereof.
In an embodiment, the metal oxide may be represented by Formula 2:
MpOq [Formula 2]
In Formula 2,
In an embodiment, the metal oxide may be represented by Formula 2-1:
Zn(1-r)M′rO [Formula 2-1]
In Formula 2-1,
In an embodiment, the metal oxide may be ZnO, ZnMgO, ZnAlO, ZnSiO, ZnYbO, TiO2, WO3, W2O3, WO2, or any combination thereof.
In an embodiment, an average diameter of the metal oxide may be in a range of about 1 nm to about 30 nm. For example, an average diameter of the metal oxide may be in a range of about 5 nm to about 15 nm. The average diameter of the metal oxide may be measured by using a dynamic light scattering (DLS) method.
In embodiments, the metal oxide may have a spherical shape. For example, the metal oxide may have a substantially spherical shape.
In a metal oxide nanoparticle, such as ZnO, multiple oxygen vacancies may be present in a crystal thereof. Due to oxygen vacancy in the nanoparticle, the inside of the nanoparticle may be an n-type, and the nanoparticle may have a high electrical conductivity. An energy level of a conduction band of the metal oxide nanoparticle may be similar to an energy level of a conduction band of quantum dots. Thus, the metal oxide nanoparticle may have excellent electron injection characteristics, and the metal oxide layer including the metal oxide nanoparticle may be used as an electron injection layer or an electron transport layer in a quantum dot light-emitting device.
However, due to an energy level caused by oxygen vacancy on the surface of the metal oxide nanoparticle, the oxygen vacancy on the surface may serve as an electron trap. Accordingly, electrons injected from an electron injection electrode may be trapped on the surface of the metal oxide. Thus, electrons may not be injected into an emission layer, and thus, electron injection and transport efficiency may be reduced. Defect-assisted non-radiative recombination or Auger-type non-radiative recombination may occur in a quantum dot emission layer adjacent to the metal oxide layer, thus deteriorating luminescence efficiency.
As the composition according to the disclosure includes the ligand represented by Formula 1, the number of electron trap sites on the surface of the metal oxide may decrease, and the efficiency of electron injection into the emission layer may increase.
Accordingly, when the composition is used in manufacturing a light-emitting device, change in the electrical characteristics over the driving time of the light-emitting device according to a chemical reaction, such as oxygen adsorption on the surface of the metal oxide, may be resolved or reduced. Thus, a light-emitting device manufactured by using the composition may exhibit excellent driving characteristics, e.g., a low driving voltage, high efficiency, and/or long lifespan.
In an embodiment, a concentration of the ligand in the composition may be 0.1 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. In an embodiment, a concentration of the ligand in the composition may be 0.5 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 0.6 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 0.7 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 0.8 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 0.9 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 1 wt % or greater, based on 100 wt % of the metal oxide nanoparticles. However, embodiments of the disclosure are not limited thereto.
In an embodiment, a concentration of the ligand in the composition may be less than 20 wt %, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 19 wt % or less, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 18 wt % or less, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 17 wt % or less, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 16 wt % or less, based on 100 wt % of the metal oxide nanoparticles. For example, a concentration of the ligand in the composition may be 15 wt % or less, based on 100 wt % of the metal oxide nanoparticles. However, embodiments of the disclosure are not limited thereto.
In an embodiment, a concentration of the ligand in the composition may be in a range of about 0.1 wt % to about 15 wt %, based on 100 wt % of the metal oxide nanoparticles.
The composition may include a solvent. The type of the solvent is not limited, as long as the solvent properly disperses the nanomaterial.
For example, the solvent may be an organic solvent.
In embodiments, the solvent may be an alcohol-based solvent, a chlorine-based solvent, an ether-based solvent, an ester-based solvent, a ketone-based solvent, an aliphatic hydrocarbon-based solvent, or an aromatic hydrocarbon-based organic solvent. However, embodiments are not limited thereto.
In embodiments, the solvent may include: an alcohol-based solvent such as methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, or t-butanol; a chlorine-based solvent such as dichloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, or o-dichlorobenzene; an ether-based solvent such as tetrahydrofuran, dioxane, anisole, 4-methylanisol, or butyl phenylether; an ester-based solvent such as ethyl acetate, butyl acetate, methyl benzoate, ethyl benzoate, butyl benzoate, or phenyl benzoate; a ketone-based solvent such as acetone, methylethylketone, cyclohexanone, or acetophenone; an aliphatic hydrocarbon-based solvent such as cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, dodecane, hexadecane, or oxadecane; an aromatic hydrocarbon-based solvent such as toluene, xylene, mesitylene, ethylbenzene, n-hexyl benzene, cyclohexyl benzene, trimethyl benzene, tetrahydronaphthalene; or any combination thereof, but embodiments are not limited thereto.
An amount of the solvent in the composition may be 80 wt % or greater to 99.5 wt % or less, based on the total weight of the composition. For example, an amount of the solvent in the composition may be 90 wt % or greater to 99 wt % or less, based on the total weight of the composition. However, embodiments of the disclosure are not limited thereto. Within any of these ranges, the nanomaterial may be properly dispersed in the composition, and a solid content concentration suitable for a solution process may be obtained.
In embodiments, a viscosity of the composition may be in a range of about 1 cP to about 10 cP. When the viscosity of the composition is within this range, the composition may be suitable for use in formation of a metal oxide layer of a light-emitting device by using a solution process.
In embodiments, a surface tension of the composition may be in a range of about 10 dynes/cm to about 40 dynes/cm. When the surface tension of the composition is within this range, the composition may be suitable for use in formation of a metal oxide layer of a light-emitting device by using a solution process.
According to embodiments, a light-emitting device 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 by using the composition described above.
In embodiments, the emission layer may include quantum dots.
In the specification, a quantum dot 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.
A 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.
Examples of a 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 a Group III-V semiconductor compound may include: a binary compound, such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and the like; a ternary compound, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, InPSb, and the like; a quaternary compound, such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GalnNSb, GaInPAs, GalnPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and the like; or any combination thereof. In an embodiment, a Group III-V semiconductor compound may further include a Group II element. Examples of a Group III-V semiconductor compound further including a Group II element may include InZnP, InGaZnP, InAlZnP, and the like.
Examples of a 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; and any combination thereof.
Examples of a 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 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.
Examples of a 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 compound, such as a binary compound, a ternary compound, and a quaternary compound may be present in a particle at a uniform concentration or at a non-uniform concentration.
In embodiments, a quantum dot may have a single structure in which the concentration of each element in the quantum dot is uniform, or a quantum dot may have a core-shell structure. When a quantum dot has a core-shell structure, a material included in the core and a material included in the shell may be different from each other.
In embodiments, 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 a quantum dot may serve as a protective layer that prevents chemical degeneration of the core to maintain semiconductor characteristics, and/or may serve as a charging layer that imparts electrophoretic characteristics to the quantum dot. The shell may be single-layered or multi-layered. An interface between the core and the shell may have a concentration gradient in which the concentration of an element in the shell decreases toward the core.
A shell of a quantum dot may include a metal oxide, a metalloid oxide, a non-metal oxide, a semiconductor compound, or any combination thereof. Examples of a metal oxide, a metalloid oxide, or a non-metal oxide 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 a 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 embodiments, the shell may have a composition that is 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 at half maximum (FWHM) of an emission spectrum equal to or less than about 45 nm. For example, the quantum dot may have a FWHM of an emission spectrum equal to or less than about 40 nm. For example, the quantum dot may have a FWHM of an emission spectrum equal to or less than about 30 nm. When the FWHM of the quantum dot is within any of these ranges, color purity or color reproducibility may be improved. Light emitted through a quantum dot may be emitted in all directions, so that a wide viewing angle may be improved.
In an embodiment, a diameter of the quantum dot may be in a range of about 1 nm to about 20 nm. When the average diameter of the quantum dots is within this range, specific characteristics as quantum dots may be achieved, and excellent dispersability of the composition may be achieved. In embodiments, a quantum dot may be in the form of a spherical particle, a pyramidal particle, a multi-arm particle, a cubic nanoparticle, a nanotube particle, a nanowire particle, a nanofiber particle, or a nanoplate particle.
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 a quantum dot emission layer. Accordingly, by using quantum dots of different sizes, a light-emitting device that emits light of various wavelengths may be implemented. In embodiments, the size of the quantum dot may be adjusted to emit red light, green light, and/or blue light. In embodiments, the sizes of quantum dots may be configured to emit white light by a combination of different colors of light.
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 that includes mixing a precursor material with an organic solvent and growing a quantum dot particle crystal. When the crystal grows, the organic solvent naturally serves as a dispersant that is coordinated on the surface of the quantum dot crystal and controls the growth of the crystal, so that the growth of quantum dot particles can be controlled through a process which costs less, and may be more readily performed than vapor deposition methods, such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE),
In embodiments, the emission layer may include a monolayer of quantum dots. In embodiments, the emission layer may include about 2 layers to about 20 layers of quantum dots.
In an embodiment, 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. For example, a thickness of the emission layer may be in a range of about 10 nm to about 100 nm.
The metal oxide layer may be a layer formed by using the composition according to an embodiment. For example, 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 interlayer 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.
In an embodiment, 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.
In an embodiment, 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. 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 layer or the electron injection layer may include the metal oxide layer.
In an embodiment, the metal oxide layer may directly contact the emission layer. In an embodiment, after the emission layer is formed, the metal oxide layer may be formed on the emission layer. In another embodiment, after the metal oxide layer is formed, the emission layer may be formed on the metal oxide layer.
In an embodiment, the emission layer may include a quantum dot, and when a metal oxide layer is formed on the emission layer including the quantum dot by using the 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. When the first electrode 110 is an anode, a 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. When the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), or any combination thereof. In embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, a material for forming the first electrode 110 may include 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 structure consisting of a single layer or a structure including multiple layers. For example, the first electrode 110 may have a three-layered structure of ITO/Ag/ITO.
The interlayer 130 may be located on the first electrode 110. The interlayer 130 may include an emission layer.
The interlayer 130 may further include a hole transport region located between the first electrode 110 and the emission layer, and an electron transport region located 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 quantum dots, or the like.
In embodiments, the interlayer 130 may include two or more emitting units stacked between the first electrode 110 and the second electrode 150, and at least one charge generation layer between adjacent units among the two or more emitting units. When the interlayer 130 includes the two or more emitting units and the at least one 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 structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a structure including multiple layers including different materials.
In an embodiment, the electron transport region may further include a metal oxide layer in addition to the materials 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.
In embodiments, 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, wherein the layers of each structure may be stacked from the first electrode 110 in its respective stated order, but the structure of the hole transport region is not limited thereto.
In embodiments, 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,
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each independently include at least one of groups represented by Formulae CY201 to CY217:
In Formulae CY201 to CY217, R10b and R10c may each independently be the same as described 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, in Formulae CY201 to CY217, ring CY201 to ring CY204 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each independently include at least one of groups represented by Formulae CY201 to CY203.
In embodiments, the compound represented by 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, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include a group represented by one of Formulae CY201 to CY203.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include a group represented by one of Formulae CY201 to CY203, and may each independently include at least one of the groups represented by Formulae CY204 to CY217.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include a group represented by one of Formulae CY201 to CY217.
In an embodiment, 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, the thickness of the hole transport region may be in a range of about 100 Å to about 4,000 Å. When 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, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å. For example, the thickness of the hole injection layer may be in a range of about 100 Å to about 1,000 Å. For example, the thickness of the hole transport layer may be in a range of about 100 Å to about 1,500 Å. When 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 a wavelength of light emitted by an emission layer, and the electron-blocking layer may block the leakage of electrons from an emission layer to a 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.
[p-Dopant]
The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of 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.
A lowest unoccupied molecular orbital (LUMO) energy level of the p-dopant may be equal to or less than about −3.5 eV.
In embodiments, the p-dopant may include a quinone derivative, a cyano group-containing compound, a compound including element EL1 and element EL2, or any combination thereof.
Examples of a quinone derivative may include TCNQ, F4-TCNQ, etc.
Examples of a cyano group-containing compound may include HAT-CN, and a compound represented by Formula 221:
In Formula 221,
R221 to R223 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, and
at least one of R221 to R223 may each independently be a C3-C60 carbocyclic group or a C1-C60 heterocyclic group, each substituted with: a cyano group; —F; —Cl; —Br; —I; a C1-C20 alkyl group substituted with a cyano group, —F, —Cl, —Br, —I, or any combination thereof; or any combination thereof.
In the compound including 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 a 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 a metalloid may include silicon (Si), antimony (Sb), tellurium (Te), etc.
Examples of a non-metal may include oxygen (O) and a halogen (for example, F, Cl, Br, I, etc.).
Examples of a compound including element EL1 and element EL2 may include a metal oxide, a metal halide (for example, a metal fluoride, a metal chloride, a metal bromide, or a metal iodide), a metalloid halide (for example, a metalloid fluoride, a metalloid chloride, a metalloid bromide, or a metalloid iodide), a metal telluride, or any combination thereof.
Examples of a 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 a metal halide may include an alkali metal halide, an alkaline earth metal halide, a transition metal halide, a post-transition metal halide, a lanthanide metal halide, etc.
Examples of an alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, LiI, NaI, KI, RbI, CsI, etc.
Examples of an 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, BaI2, etc.
Examples of a 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, CrO3, CrBr3, CrO3, 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, OS12, 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 a 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 a lanthanide metal halide may include YbF, YbF2, YbF3, SmF3, YbCl, YbCl2, YbCl3, SmCl3, YbBr, YbBr2, YbBr3, SmBr3, YbI, YbI2, YbI3, SmI3, etc.
Examples of a metalloid halide may include an antimony halide, etc. (for example, SbCl5, etc.).
Examples of a 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.).
When 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 a quantum dot as described above. In an embodiment, the green emission layer may be a quantum dot emission layer including a 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. In embodiments, at least one emission layer of the at least two emission layers may be a quantum dot emission layer including quantum dots, and the other emission layer may be an organic emission layer including organic compounds.
The electron transport region may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a structure including multiple layers including different materials.
In an embodiment, the electron transport region may further include a metal oxide layer in addition to the materials described above.
In embodiments, the electron transport region may include, for example, ZnO, TiO2, WO3, SnO2, In2O3, Nb2O5, Fe2O3, CeO2, SrTiO3, Zn2SnO4, BaSnO3, In2S3, ZnSiO, PC60BM, PC70BM, ZnMgO, AZO, GZO, 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.
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. The buffer layer, the hole-blocking layer, the electron control layer, the electron transport layer, or the electron injection layer may each be the metal oxide layer, or any combination of the buffer layer, the hole-blocking layer, the electron control layer, and the electron transport layer may be the metal oxide layer.
In embodiments, 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, wherein the layers of each structure may be stacked from an emission layer in its respective stated order, but the structure of the electron transport region is not limited thereto.
In an embodiment, 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 include a metal-free compound including at least one π electron-deficient nitrogen-containing C1-C60 cyclic group.
In an embodiment, the electron transport region may include 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 Ar601 may be linked to each other via a single bond.
In embodiments, in Formula 601, Ar601 may be a substituted or unsubstituted anthracene group.
In embodiments, the electron transport region may include a compound represented by Formula 601-1:
In Formula 601-1,
In embodiments, in Formulae 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.
In embodiments, the electron transport region may include 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, the thickness of the electron transport region may be in a range of about 160 Å to about 4,000 Å. When 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, the 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. For example, the thickness of the electron transport layer may be in a range of about 150 Å to about 500 Å. When the thickness 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 (for example, an electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.
The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of an 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 an 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 a metal ion of an alkali metal complex or with a metal ion of an alkaline earth-metal complex may include a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.
In an embodiment, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (LiQ) or Compound 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 directly contact the second electrode 150.
The electron injection layer may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a structure including multiple layers including 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: an alkali metal oxide, such as Li2O, Cs2O, or K2O; an alkali metal halide, 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), BaxCa1-xO (wherein x is a real number satisfying the condition of 0<x<1), or the like. 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 a lanthanide metal telluride. Examples of a 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: an alkali metal ion, an alkaline earth metal ion, or a rare earth metal ion; and a ligand bonded to the metal ion (for example, a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenyl benzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a 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 the electron injection layer may consist of an alkali metal-containing compound (for example, an alkali metal halide), and an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. In an embodiment, the electron injection layer may be a KI:Yb co-deposited layer, a RbI:Yb co-deposited layer, a LiF:Yb co-deposited layer, etc.
When 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. For example, the thickness of the electron injection layer may be in a range of about 3 Å to about 90 Å. When the thickness of the electron injection layer is within any of the ranges described above, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.
The second electrode 150 may be located on the interlayer 130 having a structure as described above. The second electrode 150 may be a cathode, which is an electron injection electrode. When the second electrode 150 is a cathode, a material for the second electrode 150 may include a material having a low-work function, such as a metal, an alloy, an electrically conductive compound, or any combination thereof.
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.
The light-emitting device 10 may include a first capping layer located outside the first electrode 110, and/or a second capping layer located outside the second electrode 150. In embodiments, 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 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 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 stacked in the stated order.
Light generated in an emission layer of the interlayer 130 of the light-emitting device 10 may be extracted through the first electrode 110, which may be a semi-transmissive electrode or a transmissive electrode, and through the first capping layer to the outside. Light generated in an emission layer of the interlayer 130 of the light-emitting device 10 may be extracted through the second electrode 150, which may be a semi-transmissive electrode or a transmissive electrode, and through the second capping layer to the outside.
The first capping layer and the second capping layer may each increase external luminescence efficiency according to the principle of constructive interference. Accordingly, the light extraction efficiency of the light-emitting device 10 is increased, so that the luminescence efficiency of the light-emitting device 10 may be improved.
The first capping layer and the second capping layer may each include a material having a refractive index equal to or greater than about 1.6 (with respect to a wavelength of about 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 be optionally substituted with a substituent including O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof.
In embodiments, 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 metal oxide layer according to embodiments may be included in various films. Accordingly, another embodiment provides a film that includes a metal oxide layer as described herein. The film may be, for example, an optical member (or a light control means) (for example, a color filter, a color conversion member, a capping layer, a light extraction efficiency enhancement layer, a selective light absorbing layer, a polarizing layer, a quantum dot-containing layer, or like), a light-blocking member (for example, a light reflective layer, a light absorbing layer, or the like), or a protective member (for example, an insulating layer, a dielectric layer, or the like).
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 located 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. Further details on the light-emitting device are the same as described herein. In embodiments, 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 subpixels, the color filter may include color filter areas respectively corresponding to the subpixels, and the color conversion layer may include color conversion areas respectively corresponding to the subpixels.
A pixel-defining film may be located between the subpixels to define each subpixel.
The color filter may further include color filter areas and light-shielding patterns located between the color filter areas, and the color conversion layer may further include color conversion areas and light-shielding patterns located between the color conversion areas.
The color filter areas (or the color conversion areas) may include a first area emitting first color light, a second area emitting second color light, and/or a third area emitting third color light, wherein the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths from one another. 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. In an embodiment, the color filter areas (or the color conversion areas) may include quantum dots. For example, 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. Further details on the quantum dot may be the same as described herein. The first area, the second area, and/or the third area may each include a scatterer.
In an embodiment, the light-emitting device may emit first light, the first area may absorb the first light to emit first-first color light, the second area may absorb the first light to emit second-first color light, and the third area may absorb the first light to emit third-first color light. The first-first color light, the second-first color light, and the third-first color light may have different maximum emission wavelengths. For example, 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 active layer, wherein 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, or the like.
The active layer may include crystalline silicon, amorphous silicon, an organic semiconductor, an oxide semiconductor, or the like.
The electronic apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion may be located 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 that includes a transparent glass substrate or a plastic substrate. The sealing portion may be a thin-film encapsulation layer that includes at least one of an organic layer and an inorganic layer. When the sealing portion is a thin-film encapsulation layer, the electronic apparatus may be flexible.
Various functional layers may be further included on the sealing portion, in addition to the color filter and/or the color conversion layer, according to a use of the electronic apparatus. Examples of a 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 (for example, a light-emitting apparatus) of
The substrate 100 may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer 210 may be located 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.
A TFT may be located on the buffer layer 210. The TFT may include an active layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.
The active 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 active layer 220 from the gate electrode 240 may be located on the active layer 220, and the gate electrode 240 may be located on the gate insulating film 230.
An interlayer insulating film 250 may be located on the gate electrode 240. The interlayer insulating film 250 may be located between the gate electrode 240 and the source electrode 260 to insulate the gate electrode 240 from the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to insulate the gate electrode 240 from the drain electrode 270.
The source electrode 260 and the drain electrode 270 may be located on the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose a source region and a drain region of the active layer 220, and the source electrode 260 and the drain electrode 270 may respectively contact the exposed portions of the source region and the drain region of the active layer 220.
The TFT is electrically connected to a light-emitting device to drive the light-emitting device, and is covered and protected 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 is 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 located on the passivation layer 280. The passivation layer 280 may not completely cover the drain electrode 270 and may expose a portion of the drain electrode 270. The first electrode 110 may be connected (for example, electrically connected) to the exposed portion of the drain electrode 270.
A pixel defining layer 290 including an insulating material may be located on the first electrode 110. The pixel defining layer 290 may expose a region of the first electrode 110, and an interlayer 130 may be formed on the exposed region of the first electrode 110. The pixel defining layer 290 may be a polyimide-based organic film or a polyacrylic-based organic film. Although not shown in
The second electrode 150 may be located on the interlayer 130, and a capping layer 170 may be further included on the second electrode 150. The capping layer 170 may be formed to cover the second electrode 150.
The encapsulation portion 300 may be located on the capping layer 170. The encapsulation portion 300 may be located on a light-emitting device to protect the light-emitting device from moisture and/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, polyoxymethylene, polyarylate, hexamethyldisiloxane, an acrylic resin (for example, polymethyl methacrylate, polyacrylic acid, or the like), an epoxy-based resin (for example, aliphatic glycidyl ether (AGE), or the like), or any combination thereof; or any combination of the inorganic films and the organic films.
The electronic apparatus (for example, a light-emitting apparatus) of
The electronic equipment 1, which may be an apparatus that displays a moving image or a still image, may be not only a portable electronic equipment, such as a mobile phone, a smartphone, a tablet personal computer (PC), a mobile communication terminal, an electronic notebook, an electronic book, a portable multimedia player (PMP), a navigation device, or an ultra-mobile PC (UMPC), but may also be various products, such as a television, a laptop computer, a monitor, a billboards, or an Internet of things (IOT). The electronic equipment 1 may be any product as described above or a part thereof.
In an embodiment, the electronic equipment 1 may be a wearable device, such as a smart watch, a watch phone, a glasses-type display, or a head mounted display (HMD), or a part of the wearable device. However, embodiments are not limited thereto.
Examples of the electronic equipment 1 may include a dashboard of a vehicle, a center fascia of a vehicle, a center information display (CID) on an instrument panel of a vehicle, a room mirror display that replaces a side mirror of a vehicle, an entertainment display for a rear seat of a vehicle or a display placed on the back of a front seat, a head up display (HUD) installed at the front of a vehicle or projected on a front window glass, or a computer generated hologram augmented reality head up display (CGH AR HUD).
The electronic equipment 1 may include a display area DA and a non-display area NDA outside the display area DA. A display device may implement an image through a two-dimensional array of pixels that are arranged in the display area DA.
The non-display area NDA is an area that does not display an image, and may surround (for example, entirely surround) the display area DA. A driver for providing electrical signals or power to display devices arranged in the display area DA may be arranged in the non-display area NDA. A pad, which is an area to which an electronic element or a printed circuit board may be electrically connected, may be arranged in the non-display area NDA.
In the electronic equipment 1, a length in the x-axis direction and a length in the y-axis direction may be different from each other. For example, as shown in
In embodiments, the length in the x-axis direction may be the same as the length in the y-axis direction. In embodiments, the length in the x-axis direction may be longer than the length in the y-axis direction.
Referring to
The vehicle 1000 may travel on a road or a track. The vehicle 1000 may move in a selected or given direction according to the rotation of at least one wheel. Examples of a vehicle 1000 may include a three-wheeled or four-wheeled vehicle, a construction machine, a two-wheeled vehicle, a prime mover device, a bicycle, and a train running on a track.
The vehicle 1000 may include a body having an interior and an exterior, and a chassis that is a portion excluding the body, in which mechanical apparatuses necessary for driving are installed. The exterior of the body of the vehicle 1000 may include a front panel, a bonnet, a roof panel, a rear panel, a trunk, a pillar provided at a boundary between doors, and the like. The chassis of the vehicle 1000 may include a power generating device, a power transmitting device, a driving device, a steering device, a braking device, a suspension device, a transmission device, a fuel device, front and rear wheels, left and right wheels, and the like.
The vehicle 1000 may include a side window glass 1100, a front window glass 1200, a side mirror 1300, a cluster 1400, a center fascia 1500, a passenger seat dashboard 1600, and a display device 2.
The side window glass 1100 and the front window glass 1200 may be partitioned by a pillar arranged between the side window glass 1100 and the front window glass 1200.
The side window glass 1100 may be installed on a side of the vehicle 1000. In an embodiment, the side window glass 1100 may be installed on a door of the vehicle 1000. Multiple side window glasses 1100 may be provided and may face each other. In an embodiment, the side window glass 1100 may include a first side window glass 1110 and a second side window glass 1120. In an embodiment, the first side window glass 1110 may be arranged adjacent to the cluster 1400, and the second side window glass 1120 may be arranged adjacent to the passenger seat dashboard 1600.
In an embodiment, the side window glasses 1100 may be spaced apart from each other in the x-direction or the −x-direction. For example, the first side window glass 1110 and the second side window glass 1120 may be spaced apart from each other in the x direction or the −x direction. For example, a virtual straight line L connecting the side window glasses 1100 may extend in the x-direction or the −x-direction. For example, a virtual straight line L connecting the first side window glass 1110 and the second side window glass 1120 to each other may extend in the x direction or the −x direction.
The front window glass 1200 may be installed in the front of the vehicle 1000. The front window glass 1200 may be arranged between the side window glasses 1100 facing each other.
The side mirror 1300 may provide a rear view of the vehicle 1000. The side mirror 1300 may be installed on the exterior of the body of the vehicle 1000. In an embodiment, multiple side mirrors 1300 may be provided. For example, one of the side mirrors 1300 may be arranged outside the first side window glass 1110, and another of the side mirrors 1300 may be arranged outside the second side window glass 1120.
The cluster 1400 may be arranged in front of the steering wheel. The cluster 1400 may include a tachometer, a speedometer, a coolant thermometer, a fuel gauge, a turn signal indicator, a high beam indicator, a warning light, a seat belt warning light, an odometer, a tachograph, an automatic shift selector indicator light, a door open warning light, an engine oil warning light, and/or a low fuel warning light.
The center fascia 1500 may include a control panel on which buttons for adjusting an audio device, an air conditioning device, and a seat heater are disposed. The center fascia 1500 may be arranged on a side of the cluster 1400.
A passenger seat dashboard 1600 may be spaced apart from the cluster 1400, and the center fascia 1500 may be arranged between the cluster 1400 and the passenger seat dashboard 1600. In an embodiment, the cluster 1400 may be arranged to correspond to a driver seat (not shown), and the passenger seat dashboard 1600 may be disposed to correspond to a passenger seat (not shown). In an embodiment, the cluster 1400 may be adjacent to the first side window glass 1110, and the passenger seat dashboard 1600 may be adjacent to the second side window glass 1120.
In an embodiment, the display device 2 may include a display panel 3, and the display panel 3 may display an image. The display device 2 may be arranged inside the vehicle 1000. In an embodiment, the display device 2 may be arranged between the side window glasses 1100 facing each other. The display device 2 may be arranged on at least one of the cluster 1400, the center fascia 1500, and the passenger seat dashboard 1600.
The display device 2 may include an organic light-emitting display device, an inorganic electroluminescent (EL) display device, a quantum dot display device, or the like. Hereinafter, an organic light-emitting display device including the light-emitting device according to an embodiment will be described as an example of the display device 2. However, various types of display devices as described above may be used in embodiments.
Referring to
Referring to
Referring to
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 selected region by using one or more suitable methods selected from vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, and laser-induced thermal imaging.
When layers constituting the hole transport region, an emission layer, and layers constituting 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 atoms as the only ring-forming atoms and having three to sixty carbon atoms. The term “C1-C60 heterocyclic group” as used herein may be a cyclic group that has one to sixty carbon atoms and further has, in addition to a carbon atom, at least one 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, a C1-C60 heterocyclic group may have 3 to 61 ring-forming atoms.
The term “cyclic group” as used herein may be a C3-C60 carbocyclic group or a C1-C60 heterocyclic group.
The term “π electron-rich C3-C60 cyclic group” as used herein may be a cyclic group that has three to sixty carbon atoms and may 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 one to sixty carbon atoms and may include *—N═*′ as a ring-forming moiety.
In embodiments,
The terms “cyclic group”, “C3-C60 carbocyclic group”, “C1-C60 heterocyclic group”, “π electron-rich C3-C60 cyclic group”, and “π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein 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 a monovalent C3-C60 carbocyclic group or a 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. Examples of a divalent C3-C60 carbocyclic group or a 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 divalent non-aromatic condensed heteropolycyclic group.
The term “C1-C60 alkyl group” as used herein may be a linear or branched monovalent aliphatic hydrocarbon group that has one to sixty 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 a 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 a terminus of a C2-C60 alkyl group, and examples thereof may include an ethynyl group, a propynyl group, and the like. 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 A101 may be a 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 having 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms, and examples thereof 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 three to ten carbon atoms and at least one carbon-carbon double bond in the cyclic structure 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 having 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 in the cyclic structure thereof. Examples of a C1-C10 heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, a 2,3-dihydrothiophenyl group, etc. 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 a 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. When the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the respective two or more 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 a 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. When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the respective two or more 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 molecular structure as a whole. Examples of a 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 indeno anthracenyl 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 described above.
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 no aromaticity in its molecular structure as a whole. Examples of a 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 described above.
The term “C6-C60 aryloxy group” as used herein may be a group represented by —O(A102) (wherein A102 may be a C6-C60 aryl group), and the term “C6-C60 arylthio group” as used herein may be a group represented by —S(A103) (wherein A103 may be a C6-C60 aryl group).
The term “C7-C60 aryl alkyl group” as used herein may be a group represented by -(A104)(A105) (wherein A104 may be a C1-C54 alkylene group, and A105 may be a C6-C59 aryl group). The term “C2-C60 heteroaryl alkyl group” as used herein may be a group represented by -(A106)(A107) (wherein A106 may be a C1-C59 alkylene group, and A107 may be a C1-C59 heteroaryl group).
In the specification, the group “R10a” may be:
In the specification, Q1 to Q3, Q11 to Q13, Q21 to Q23, and Q31 to Q33 may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; C1-C60 alkyl group; C2-C60 alkenyl group; C2-C60 alkynyl group; C1-C60 alkoxy group; or 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.
The term “heteroatom” as used herein may be any atom other than a carbon atom or a hydrogen atom. Examples of a heteroatom may include B, O, S, N, P, Si, B, Ge, Se, and any combinations thereof.
In the specification, the term “Ph” refers to a phenyl group, the term “Me” refers to a methyl group, the term “Et” refers to an ethyl group, the terms “tert-Bu” and “But” each refers to a tert-butyl group, and the term “OMe” refers to a methoxy group.
The term “biphenyl group” as used herein may be a “phenyl group substituted with a phenyl group.” For example, a “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, a “terphenyl group” may be a substituted phenyl group having, as a substituent, a C6-C60 aryl group substituted with a C6-C60 aryl group.
In the specification, 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.
In the specification, the terms “x-axis”, “y-axis”, and “z-axis” are not limited to three axes in an orthogonal coordinate system (for example, a Cartesian coordinate system), and may be interpreted in a broader sense than the aforementioned three axes in an orthogonal coordinate system. For example, the x-axis, y-axis, and z-axis may describe axes that are orthogonal to each other, or may describe axes that are in different directions that are not orthogonal to each other.
Hereinafter, compositions and light-emitting devices according to embodiments will be described in detail with reference to the following Preparation Examples and Examples.
For synthesis of ZnMgO nanoparticles, zinc acetate dihydrate (1.0427 g) and magnesium acetate tetrahydrate (0.0536 g) were dissolved in 30 mL of dimethyl sulfoxide and stirred. A solution obtained by dissolving 1.359 g of tetramethylammonium hydroxide pentahydrate (TMAH) in 10 mL of ethanol was added to the foregoing solution and stirred intensively. The mixed solution was maintained while being stirred at 30° C. for 2 hours and 30 minutes, and the synthesized ZnMgO nanoparticles were precipitated for about an hour. The solution was subjected to centrifugation at 4,000 rpm for about 5 minutes in a centrifuge, and the final precipitated nanoparticles were dispersed in ethanol to prepare ink.
2-hydroxyethyl methacrylate (HEMA) was added to the mixed solution prepared in Comparative Preparation Example 1 in the amount of 0.5 wt % based on 100 wt % of ZnMgO nanoparticles and stirred sufficiently at 30° C. for about 12 hours. The stirred solution was a final mixed solution of Preparation Example 1 to prepare ink.
HEMA was added to the mixed solution prepared in Comparative Preparation Example 1 in the amount of 1 wt % based on 100 wt % of ZnMgO nanoparticles and stirred sufficiently at 30° C. for about 12 hours. The stirred solution was a final mixed solution of Preparation Example 2 to prepare ink.
HEMA was added to the mixed solution prepared in Comparative Preparation Example 1 in the amount of 5 wt % based on 100 wt % of ZnMgO nanoparticles and stirred sufficiently at 30° C. for about 12 hours. The stirred solution was a final mixed solution of Preparation Example 3 to prepare ink.
HEMA was added to the mixed solution prepared in Comparative Preparation Example 1 in the amount of 10 wt % based on 100 wt % of ZnMgO nanoparticles and stirred sufficiently at 30° C. for about 12 hours. The stirred solution was a final mixed solution of Preparation Example 4 to prepare ink.
HEMA was added to the mixed solution prepared in Comparative Preparation Example 1 in the amount of 20 wt % based on 100 wt % of ZnMgO nanoparticles and stirred sufficiently at 30° C. for about 12 hours. The stirred solution was a final mixed solution of Preparation Example 5 to prepare ink.
Acrylate was added to the mixed solution prepared in Comparative Preparation Example 1 in the amount of 5 wt % based on 100 wt % of ZnMgO nanoparticles and stirred at 30° C. for about 12 hours. The stirred solution was a final mixed solution of Comparative Preparation Example 2 to prepare ink.
The ink of Comparative Preparation Example 1 was applied on a glass substrate by spin coating at a speed of 2,000 rpm, and the glass substrate was dried at 100° C. for 30 minutes in a nitrogen (N2) atmosphere to form Film A for measurement. Film B was formed by applying the ink of Preparation Example 3 on a glass substrate in the same manner.
The ink of Comparative Preparation Example 1 was applied on a glass substrate by spin coating at a speed of 2,000 rpm, and the glass substrate was dried at 100° C. for 30 minutes in a nitrogen (N2) atmosphere to form a film for measurement. A red quantum dot solution dispersed in toluene at a concentration of 10 mg/mL was applied thereon by spin coating at a speed of 4,000 rpm, and the glass substrate was dried at 70° C. for 10 minutes in the nitrogen atmosphere to form Film C1. Film C2 was formed in the same manner as in the manufacture of Film C1, except that the ink of Comparative Preparation Example 2 was used instead of the ink of Comparative Preparation Example 1.
The ink of Preparation Example 3 was applied on a glass substrate by spin coating at a speed of 2,000 rpm, and the substrate was dried at 100° C. for 30 minutes in a nitrogen atmosphere to form a film for measurement. A red quantum dot solution dispersed in toluene at a concentration of 10 mg/mL was applied thereon by spin coating at a speed of 4,000 rpm, and the substrate was dried at 70° C. for 10 minutes in the nitrogen atmosphere to form Film D.
Atomic force microscope (AFM) measurement was conducted for observation of surface roughness, and the AFM measurement was performed in a non-contact manner by using the NX10 model of Park systems. The result of AFM observation of the manufactured Film A is shown in
Referring to
The contact angles of Films A and B were measured by using a contact angle measuring instrument (DSA100 model of KRUSS). For the sake of accuracy, the measurement was conducted immediately after Films A and B were manufactured with minimum atmospheric exposure. The contact angle measurement results of the manufactured Films A and B are respectively shown in
Referring to
The photoluminescence (PL) of Films A and B was measured, and the results thereof are shown in
The PL of Films C1, C2, and D was measured, and the results thereof are shown in
The X-ray photoelectron spectroscopy (XPS) analysis was conducted by using equipment for electron spectroscopy for chemical analysis (ESCA) of Kratos Axis Supra. Films A and B were prepared for the XPS surface analysis, and through the Gaussian decomposition method, the sites of metal oxide lattice (OM), oxygen vacancy (OV), and oxygen bonded to hydroxide (OH) were respectively designated as 529.1 eV, 530.8 eV, and 531.8 eV.
The oxygen 1s peaks of Films A and B were measured by XPS, and the results thereof are shown in
The ultraviolet photoelectron spectroscopy (UPS) analysis was conducted by using equipment for ESCA of Kratos Axis Supra. Films A and B were prepared for the UPS surface analysis, and the energy levels were measured by considering the clear cut-off value of the lowest bond energy.
The energy levels of Films A and B were measured, and the results thereof are shown in
Electron only devices (EODs) having an ITO/Film C/Al (EOD-C) structure or an ITO/Film D/Al (EOD-D) structure were manufactured, and the electric characteristics thereof were compared by applying a voltage to the EODs and measuring a current density. The results of current density measurement of the EODs are shown in Table 12.
Referring to
An ITO glass substrate (50 mm×50 mm, 15 Ω/cm, Samsung-Corning product) was sequentially sonicated using distilled water and isopropanol, and cleaned by exposure to UV ozone for 30 minutes. The ink according to Preparation Example 1 was applied on a glass substrate by spin coating with a transparent electrode line attached thereon after the cleaning to form a film having a thickness of about 300 Å to about 500 Å, and baked at 120° C. for 30 minutes to form an electron transport layer.
The composition including InP quantum dots was applied on the electron transport layer by spin coating to form a film having a thickness of about 150 Å to about 250 Å, and baked at 140° C. for 10 minutes to form an emission layer.
Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) was vacuum-deposited on the emission layer to form a hole transfer layer having a thickness of 500 Å, and MoO3 was vacuum-deposited on the hole transfer layer to form a hole injection layer having a thickness of 100 Å. Al was vacuum-deposited on the hole injection layer to form an anode having a thickness of 1,300 Å, thereby completing the manufacture of a light-emitting device.
Light-emitting devices were manufactured in the same manner as in Example 1, except that each ink shown in Table 2 was used when forming an electron transport layer.
The external quantum efficiency (EQE) at a current density of 10 mA/cm2 and lifespan (hr) of the light-emitting devices of Examples 1 to 5 and Comparative Example 1 were measured, and the results thereof are shown in
Referring to
Referring to
A light-emitting device using the composition may have excellent driving voltage, luminescence efficiency, and lifespan characteristics, and by using the light-emitting device, a high-quality electronic apparatus may be manufactured.
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 the purposes of limitation. In some instances, as would be apparent by 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 |
|---|---|---|---|
| 10-2023-0183479 | Dec 2023 | KR | national |
