Light emitting device and electronic apparatus comprising same

Abstract

A first electrode; a second electrode facing the first electrode; and an intermediate layer interposed between the first electrode and the second electrode and including a light-emitting layer; comprising A light-emitting device is disclosed, wherein the above intermediate layer comprises a multilayer film consisting of an odd number of layers, and the multilayer film is formed by alternately stacking layers with different refractive indices.

Description

Technology Field

[0001] This relates to a light-emitting element and an electronic device including the same. Background Technology

[0002] The light emitting device is a self-emissive device, and compared to conventional devices, it has a wide viewing angle and excellent contrast, as well as a fast response time and excellent characteristics of brightness, driving voltage, and response speed.

[0003] The light-emitting device may have a structure in which a first electrode is disposed on a substrate, and a hole transport region, a light-emitting layer, an electron transport region, and a second electrode are sequentially formed on the first electrode. Holes injected from the first electrode move to the light-emitting layer via the hole transport region, and electrons injected from the second electrode move to the light-emitting layer via the electron transport region. Carriers such as holes and electrons recombine in the light-emitting layer region to generate light. The problem to be solved

[0004] The purpose is to provide light-emitting devices with improved efficiency and lifespan. means of solving the problem

[0005] According to one aspect,

[0006] First electrode;

[0007] A second electrode facing the first electrode; and

[0008] An intermediate layer interposed between the first electrode and the second electrode and including a light-emitting layer; comprising

[0009] The above intermediate layer comprises a multilayer film consisting of an odd number of layers, and

[0010] The above multilayer film is provided with a light-emitting device formed by alternately stacking layers with different refractive indices:

[0011] According to other aspects of work,

[0012] An electronic device including the above-mentioned light-emitting element is provided. Effects of the invention

[0013] A light-emitting device according to one embodiment shows improved efficiency and lifespan. Brief explanation of the drawing

[0014] FIG. 1 is a diagram schematically showing the structure of a light-emitting element according to one embodiment. FIG. 2 is a cross-sectional view of an electronic device according to one embodiment of the present invention. FIG. 3 is a cross-sectional view of an electronic device according to another embodiment of the present invention. Specific details for implementing the invention

[0015] A light-emitting element according to one aspect

[0016] First electrode;

[0017] A second electrode facing the first electrode; and

[0018] An intermediate layer interposed between the first electrode and the second electrode and including a light-emitting layer; comprising

[0019] The above intermediate layer comprises a multilayer film consisting of an odd number of layers, and

[0020] The above multilayer film can be formed by alternately stacking layers with different refractive indices.

[0021] Although fluorescent and phosphorescent materials have been used in conventional organic light-emitting diodes (OLEDs), only fluorescent materials have been used for blue devices so far. Fluorescent materials have a theoretical quantum efficiency of 25%, which presents a problem of lower efficiency performance compared to phosphorescent or delayed fluorescence. Therefore, it is necessary to develop blue phosphorescent or delayed fluorescence devices to maximize device performance. However, blue phosphorescent / delayed fluorescence devices still face difficulties in ensuring lifespan, and it is necessary to overcome this.

[0022] Generally, in organic light-emitting diodes, the light-emitting layer is composed of a single layer, and the efficiency and lifespan of the device are improved by controlling the concentration gradient within the light-emitting layer or the host / dopant compounds of the light-emitting layer, or by introducing an auxiliary layer of a different material in an adjacent layer.

[0023] A light-emitting device according to one embodiment of the present invention applies a phosphorescent or delayed-fluorescent material as a dopant to improve the internal quantum efficiency of the device, and applies a multilayer film in a cascading form from the hole transport layer to the auxiliary layer in front of the light-emitting layer to facilitate hole injection. In addition, the refractive index of the multilayer film is adjusted so that the light efficiency of the light generated in the light-emitting layer is improved through constructive interference.

[0024] According to one embodiment, the multilayer film may exist between the first electrode and the light-emitting layer.

[0025] For example, the first electrode is an anode and the second electrode is a cathode, and the intermediate layer is disposed between the first electrode and the light-emitting layer and may further include a hole transport region comprising a hole injection layer, a hole transport layer, an electron blocking layer, an auxiliary layer, or any combination thereof. For example, the multilayer film may exist in the hole transport region.

[0026] For example, the first electrode is an anode and the second electrode is a cathode, and the intermediate layer is disposed between the second electrode and the light-emitting layer and may further include an electron transport region comprising a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

[0027] According to one embodiment, the multilayer film may be a three-layer structure in which a first layer, a second layer, and a third layer are stacked in order; or a five-layer structure in which a first layer, a second layer, a third layer, a fourth layer, and a fifth layer are stacked in order.

[0028] According to one embodiment, the intermediate layer further includes a hole injection layer, and the multilayer film can be in direct contact with the hole injection layer and the light-emitting layer.

[0029] For example, if the above multilayer film has a three-layer structure, the first layer may be in direct contact with the hole injection layer and the third layer may be in direct contact with the light-emitting layer, or the third layer may be in direct contact with the hole injection layer and the first layer may be in direct contact with the light-emitting layer.

[0030] For example, if the above multilayer film has a 5-layer structure, the first layer may be in direct contact with the hole injection layer and the fifth layer may be in direct contact with the light-emitting layer, or the fifth layer may be in direct contact with the hole injection layer and the first layer may be in direct contact with the light-emitting layer.

[0031] According to one embodiment, the multilayer film may include a hole transport layer and an auxiliary layer. For example, the multilayer film may consist of a hole transport layer and an auxiliary layer, and the total number of the hole transport layer and the auxiliary layer may be an odd number.

[0032] The compounds included in the hole transport layer and auxiliary layer mentioned above will be described later.

[0033] According to one embodiment, the multilayer film has a three-layer structure in which a first layer, a second layer, and a third layer are stacked in order, and

[0034] The above first layer is a first hole transport layer and the second layer is a second hole transport layer, and

[0035] The above third layer may be a first auxiliary layer.

[0036] For example, the refractive indices of the first and third layers may each be smaller than the refractive index of the second layer. For example, the multilayer film may include a structure of a first hole transport layer [low refractive index] / a second hole transport layer [high refractive index] / a first auxiliary layer [low refractive index].

[0037] According to one embodiment, the multilayer film has a three-layer structure in which a first layer, a second layer, and a third layer are stacked in order, and

[0038] The above first layer is a first hole transport layer, and

[0039] The above second layer may be the first auxiliary layer and the third layer may be the second auxiliary layer.

[0040] For example, the refractive indices of the first and third layers may each be smaller than the refractive index of the second layer. For example, the multilayer film may include a structure of a first hole transport layer [low refractive index] / a first auxiliary layer [high refractive index] / a second auxiliary layer [low refractive index].

[0041] For example, the compounds of the first and third layers may be the same or different from each other.

[0042] According to one embodiment, the multilayer film has a five-layer structure in which a first layer, a second layer, a third layer, a fourth layer, and a fifth layer are stacked in order, and

[0043] The above first layer is a first hole transport layer and the second layer is a second hole transport layer, and

[0044] The above third layer may be the first auxiliary layer, the fourth layer may be the second auxiliary layer, and the fifth layer may be the third auxiliary layer.

[0045] For example, the refractive indices of the first and fifth layers may each be smaller than the refractive indices of the second and fourth layers. For example, the multilayer film may include a structure of a first hole transport layer [low refractive index] / a second hole transport layer [high refractive index] / a first auxiliary layer [low refractive index] / a second auxiliary layer [high refractive index] / a third auxiliary layer [low refractive index].

[0046] According to one embodiment, the multilayer film has a five-layer structure in which a first layer, a second layer, a third layer, a fourth layer, and a fifth layer are stacked in order, and

[0047] The above first layer is a first hole transport layer, the second layer is a second hole transport layer, and the third layer is a third hole transport layer, and

[0048] The above-mentioned fourth layer may be the first auxiliary layer and the fifth layer may be the second auxiliary layer.

[0049] For example, the refractive indices of the first and fifth layers may each be smaller than the refractive indices of the second and fourth layers. For example, the multilayer film may include a structure of a first hole transport layer [low refractive index] / a second hole transport layer [high refractive index] / a third hole transport layer [low refractive index] / a first auxiliary layer [high refractive index] / a second auxiliary layer [low refractive index].

[0050] The above low refractive index may be, for example, a value of 1.7 to 1.9, and the above high refractive index may be, for example, a value greater than 1.9. The above high refractive index may be, for example, a value greater than 1.9 to 2.5.

[0051] For example, the compounds of the first, third, and fifth layers may be the same or different from each other. For example, the compounds of the second and fourth layers may be the same or different from each other.

[0052] According to one embodiment, the multilayer film has a three-layer structure in which a first layer, a second layer, and a third layer are stacked in order, and the thickness of the second layer may be thicker than the thickness of the first layer and the third layer. The thicknesses of the first layer, the second layer, and the third layer may be independently 10 to 700 Å.

[0053] According to one embodiment, the multilayer film has a five-layer structure in which a first layer, a second layer, a third layer, a fourth layer, and a fifth layer are stacked in order, and

[0054] The thickness of at least one of the second, third, and fourth layers may be thicker than the thickness of the first and fifth layers. The thicknesses of the first to fifth layers may be independently 10 to 700 Å.

[0055] According to one embodiment of the present invention, the multilayer film of the light-emitting device is structured to consist of an odd number of layers, and when the refractive index of each layer is as described above and the thickness of the layer inside the multilayer film is thicker than the thickness of the layer outside the multilayer film, the efficiency of the light-emitting device is improved by the occurrence of a resonance effect.

[0056] According to one embodiment, the light-emitting layer may include a hole-transporting host, an electron-transporting host, and a dopant.

[0057] The hole-transporting host mentioned above may be, for example, a carbazole-based or amine-based compound containing an electron-giving group.

[0058] The above electron transportable host may be, for example, a compound containing an electron-stealing group or a bipolar compound. A bipolar compound refers to a compound containing both an electron-donating group and an electron-stealing group.

[0059] The above hosts will be explained in more detail later.

[0060] According to one embodiment, the dopant may include a fluorescent dopant, a delayed fluorescent dopant, a phosphorescent dopant, or any combination thereof.

[0061] The above dopants will be explained in more detail later.

[0062] According to one embodiment, the hole transport host content in the light-emitting layer may be greater than the electron transport host content. For example, the ratio of the hole transport host content to the electron transport host content may be 10:1.0 to 5.0:4.9 (weight ratio). When the content ratio of the hole transport host and the electron transport host is within the above range, the lifespan of the light-emitting device, etc., is optimized.

[0063] An electronic device according to another aspect may include the light-emitting element.

[0064] According to one embodiment, the electronic device comprises the light-emitting element and the thin-film transistor, and the thin-film transistor comprises a source electrode and a drain electrode, and

[0065] The first electrode of the light-emitting element can be electrically connected to at least one of the source electrode and the drain electrode of the thin-film transistor.

[0066] According to one embodiment, the electronic device may further include a color filter, a color conversion layer, a touchscreen layer, a polarizing layer, or any combination thereof.

[0067] In this specification, "intermediate layer" is a term referring to a single and / or multiple layers disposed between the first electrode and the second electrode of the light-emitting element.

[0068] [Explanation of Fig. 1]

[0069] FIG. 1 schematically illustrates a cross-sectional view of a light-emitting element (10) according to one embodiment of the present invention. The light-emitting element (10) includes a first electrode (110), an intermediate layer (130), and a second electrode (150).

[0070] Hereinafter, the structure and manufacturing method of a light-emitting element (10) according to one embodiment of the present invention are described as follows with reference to FIG. 1.

[0071] [First electrode (110)]

[0072] A substrate may be additionally disposed on the lower part of the first electrode (110) of FIG. 1 or on the upper part of the second electrode (150). As the substrate, a glass substrate or a plastic substrate may be used. Alternatively, the substrate may be a flexible substrate and may include a plastic with excellent heat resistance and durability, such as polyimide, polyethylene terephthalate (PET), polycarbonate, polyethylene naphtalate, polyarylate (PAR), polyetherimide, or any combination thereof.

[0073] The first electrode (110) can be formed, for example, by providing a material for the first electrode on the substrate using a deposition method or a sputtering method. When the first electrode (110) is an anode, a material with a high work function that facilitates hole injection can be used as the material for the first electrode.

[0074] The first electrode (110) may be a reflective electrode, a semi-transparent electrode, or a transparent electrode. To form the first electrode (110) which is a transparent electrode, indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), or any combination thereof may be used as the material for the first electrode. Alternatively, to form the first electrode (110) which is a semi-transparent electrode or a reflective electrode, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof may be used as the material for the first electrode.

[0075] The first electrode (110) may have a single-layer structure consisting of a single layer or a multi-layer structure including multiple layers. For example, the first electrode (110) may have a three-layer structure of ITO / Ag / ITO.

[0076] [Middle layer (130)]

[0077] An intermediate layer (130) is disposed on the upper portion of the first electrode (110). The intermediate layer (130) includes a light-emitting layer.

[0078] The above intermediate layer (130) may further include a hole transport region disposed between the first electrode (110) and the light-emitting layer and an electron transport region disposed between the light-emitting layer and the second electrode (150).

[0079] The above intermediate layer (130) may further include, in addition to various organic materials, metal-containing compounds such as organometallic compounds, inorganic materials such as quantum dots, etc.

[0080] Meanwhile, the intermediate layer (130) may include i) two or more light-emitting layers sequentially stacked between the first electrode (110) and the second electrode (150), and ii) a charge generation layer disposed between the two light-emitting layers. When the intermediate layer (130) includes the light-emitting layer and the charge generation layer as described above, the light-emitting element (10) may be a tandem light-emitting element.

[0081] [Middle layer (130) with a fixed transport area]

[0082] The hole transport region may have i) a monolayer structure consisting of a single layer made of a single material, ii) a monolayer structure consisting of a single layer containing multiple different materials, or iii) a multilayer structure including multiple layers containing multiple different materials.

[0083] The hole transport region above may include a hole injection layer, a hole transport layer, an auxiliary layer, an electron blocking layer, or any combination thereof.

[0084] For example, the hole transport region may have a multilayer structure of a hole injection layer / hole transport layer, a hole injection layer / hole transport layer / auxiliary layer, a hole injection layer / auxiliary layer, a hole transport layer / auxiliary layer, or a hole injection layer / hole transport layer / electron blocking layer stacked sequentially from the first electrode (110).

[0085] The above-mentioned hole transport layer and auxiliary layer may refer to the details described above.

[0086] The hole transport region (e.g., the hole transport layer and / or auxiliary layer) may comprise a compound represented by the following chemical formula 201, a compound represented by the following chemical formula 202, or any combination thereof:

[0087] <Chemical Formula 201>

[0088]

[0089] <Chemical Formula 202>

[0090]

[0091] Among the above chemical formulas 201 and 202,

[0092] L 201 to L 204 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0093] L 205 은, *-O-*', *-S-*', *-N(Q 201 )-*', at least one R 10a C1-C substituted or unsubstituted 20 alkylene group, at least one R 10a C2-C substituted or unsubstituted 20 alkenylene group, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0094] xa1 to xa4 are independently one of integers 0 to 5, and

[0095] xa5 is one of integers from 1 to 10, and

[0096] R 201 to R 204and Q 201 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0097] R 201 and R 202 is optionally a single bond, at least one R 10a A C1-C5 alkylene group substituted or unsubstituted with or at least one R 10a Connected to each other through C2-C5 alkenylene groups substituted or unsubstituted, at least one R 10a C8-C substituted or unsubstituted 60 It can form polycyclic groups (e.g., carbazole groups, etc.) (e.g., refer to the following compound HT16, etc.),

[0098] R 203 and R 204 is optionally a single bond, at least one R 10a A C1-C5 alkylene group substituted or unsubstituted with, or at least one R 10a Connected to each other through C2-C5 alkenylene groups substituted or unsubstituted, at least one R 10a C8-C substituted or unsubstituted 60 It can form polycyclic groups, and

[0099] na1 can be one of integers from 1 to 4.

[0100] Meanwhile, the auxiliary layer may further include a hole-transporting host compound in addition to the compound represented by Chemical Formula 201, the compound represented by Chemical Formula 202, or any combination thereof.

[0101] For example, each of the above chemical formulas 201 and 202 may include at least one of the group represented by the following chemical formulas CY201 to CY217:

[0102]

[0103] Among the above chemical formulas CY201 to CY217, R 10b and R 10c Descriptions of each of R in this specification 10a Refer to the explanation for, and ring CY 201 Inner ring CY 204 are independently of each other, C3-C 20 Carbocyclic group or C1-C 20 It is a heterocyclic group, and at least one hydrogen of the chemical formulas CY201 to CY217 is R as described in this specification. 10a It can be substituted or unsubstituted.

[0104] According to one embodiment, among the chemical formulas CY201 to CY217, the ring CY 201 Inner ring CY 204 It can be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group independently of each other.

[0105] According to another embodiment, each of the above formulas 201 and 202 may include at least one of the group represented by the formulas CY201 to CY203.

[0106] According to another embodiment, the formula 201 may each include at least one of the group represented by formulas CY201 to CY203 and at least one of the group represented by formulas CY204 to CY217.

[0107] According to another embodiment, xa1 in the above chemical formula 201 is 1, and R 201 is a group represented by one of the above chemical formulas CY201 to CY203, xa2 is 0, and R 202may be a group represented by one of the above chemical formulas CY204 to CY207.

[0108] According to another embodiment, each of the above formulas 201 and 202 may not include the group represented by the above formulas CY201 to CY203.

[0109] According to another embodiment, each of the above formulas 201 and 202 may not include the group represented by formulas CY201 to CY203 and may include at least one of the group represented by formulas CY204 to CY217.

[0110] As another example, each of the above chemical formulas 201 and 202 may not include the group represented by the above chemical formulas CY201 to CY217.

[0111] For example, the hole transport layer and the auxiliary layer may independently comprise any one of the following compounds:

[0112]

[0113]

[0114]

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121] The thickness of the hole transport region may be about 50 Å to about 10,000 Å, for example, about 100 Å to about 4,000 Å. If the hole transport region includes a hole injection layer, a hole transport layer, or any combination thereof, the thickness of the hole injection layer may be about 10 Å to about 9,000 Å, for example, about 20 Å to about 100 Å. When the thickness of the hole transport region and the hole injection layer satisfies the ranges described above, satisfactory hole transport characteristics can be obtained without a substantial increase in driving voltage.

[0122] The above auxiliary layer is a layer that increases light emission efficiency by compensating for the optical resonance distance according to the wavelength of light emitted from the light-emitting layer, and the above electron blocking layer is a layer that prevents electron leakage from the hole transport region to the light-emitting layer. A material that can be included in the aforementioned hole transport region may be included in the light-emitting auxiliary layer and the electron blocking layer.

[0123] [p-dopant]

[0124] The hole transport region (e.g., hole injection layer) may include a charge-generating material to improve conductivity in addition to the material described above. The charge-generating material may be uniformly or non-uniformly dispersed within the hole transport region (e.g., in the form of a single layer consisting of the charge-generating material).

[0125] The above charge-generating material may be, for example, a p-dopant.

[0126] For example, the LUMO energy level of the above p-dopant may be -3.5 eV or less.

[0127] According to one embodiment, the p-dopant may include a quinone derivative, a cyano group-containing compound, an element EL1 and an element EL2-containing compound, or any combination thereof.

[0128] Examples of the above quinone derivatives may include TCNQ, F4-TCNQ, etc.

[0129] Examples of the above cyano group-containing compounds may include HAT-CN, compounds represented by the following chemical formula 221, etc.

[0130]

[0131] <Chemical Formula 221>

[0132]

[0133] Of the above chemical formula 221,

[0134] R 221 to R 223 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0135] The above R 221 to R 223 At least one of which is independently substituted with a cyano group; -F; -Cl; -Br; -I; a cyano group, -F, -Cl, -Br, -I, or any combination thereof C1-C 20 C3-C substituted with an alkyl group; or any combination thereof. 60 Carbocyclic group or C1-C 60 It can be a heterocyclic group.

[0136] Among the above-mentioned compounds containing elements EL1 and EL2, element EL1 may be a metal, a metalloid, or a combination thereof, and element EL2 may be a nonmetal, a metalloid, or a combination thereof.

[0137] Examples of the above metals are alkali metals (e.g., lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc.); alkaline earth metals (e.g., beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), etc.); transition metals (e.g., 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.); Transition metals (e.g., zinc (Zn), indium (In), tin (Sn), etc.); lanthanide metals (e.g., 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.); etc. may be included.

[0138] Examples of the above metalloids may include silicon (Si), antimony (Sb), tellurium (Te), etc.

[0139] Examples of the above nonmetals may include oxygen (O), halogens (e.g., F, Cl, Br, I, etc.).

[0140] For example, the above-mentioned element EL1 and element EL2-containing compounds may include metal oxides, metal halides (e.g., metal fluorides, metal chlorides, metal bromides, metal iodides, etc.), metal halides (e.g., metal fluorides, metal chlorides, metal bromides, metal iodides, etc.), metal tellurides, or any combination thereof.

[0141] Examples of the above metal oxides may include tungsten oxide (e.g., WO, W2O3, WO2, WO3, W2O5, etc.), vanadium oxide (e.g., VO, V2O3, VO2, V2O5, etc.), molybdenum oxide (MoO, Mo2O3, MoO2, MoO3, Mo2O5, etc.), rhenium oxide (e.g., ReO3, etc.).

[0142] Examples of the above metal halides may include alkali metal halides, alkaline earth metal halides, transition metal halides, post-transition metal halides, lanthanide metal halides, etc.

[0143] Examples of the above alkali metal halides may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, LiI, NaI, KI, RbI, CsI, etc.

[0144] Examples of the above alkaline earth metal halides may include BeF2, MgF2, CaF2, SrF2, BaF2, BeCl2, MgCl2, CaCl2, SrCl2, BaCl2, BeBr2, MgBr2, CaBr2, SrBr2, BaBr2, BeI2, MgI2, CaI2, SrI2, BaI2, etc.

[0145] Examples of the above transition metal halides include titanium halides (e.g., TiF4, TiCl4, TiBr4, TiI4, etc.), zirconium halides (e.g., ZrF4, ZrCl4, ZrBr4, ZrI4, etc.), hafnium halides (e.g., HfF4, HfCl4, HfBr4, HfI4, etc.), vanadium halides (e.g., VF3, VCl3, VBr3, VI3, etc.), niobium halides (e.g., NbF3, NbCl3, NbBr3, NbI3, etc.), tantalum halides (e.g., TaF3, TaCl3, TaBr3, TaI3, etc.), chromium halides (e.g., CrF3, CrCl3, CrBr3, CrI3, etc.), molybdenum halides (e.g., MoF3, MoCl3, MoBr3, MoI3, etc.), and tungsten. Halides (e.g., WF3, WCl3, WBr3, WI3, etc.), manganese halides (e.g., MnF2, MnCl2, MnBr2, MnI2, etc.), technetium halides (e.g., TcF2, TcCl2, TcBr2, TcI2, etc.), rhenium halides (e.g., ReF2, ReCl2, ReBr2, ReI2, etc.), iron halides (e.g., FeF2, FeCl2, FeBr2, FeI2, etc.), ruthenium halides (e.g., RuF2, RuCl2, RuBr2, RuI2, etc.), osmium halides (e.g., OsF2, OsCl2, OsBr2, OsI2, etc.), cobalt halides (e.g., CoF2, CoCl2, CoBr2, CoI2, etc.), rhodium halides (e.g., RhF2, RhCl2, RhBr2, RhI2, etc.), iridium halides (e.g., IrF2, IrCl2, IrBr2, IrI2, etc.), nickel halides (e.g., NiF2, NiCl2, NiBr2, NiI2, etc.), palladium halides (e.g., PdF2, PdCl2, PdBr2, PdI2, etc.), platinum halides (e.g., PtF2, PtCl2, PtBr2, PtI2, etc.), copper halides (e.g., CuF, CuCl, CuBr, CuI, etc.),It may include silver halides (e.g., AgF, AgCl, AgBr, AgI, etc.), gold halides (e.g., AuF, AuCl, AuBr, AuI, etc.), etc.

[0146] Examples of the above-mentioned transition metal halides may include zinc halides (e.g., ZnF2, ZnCl2, ZnBr2, ZnI2, etc.), indium halides (e.g., InI3, etc.), tin halides (e.g., SnI2, etc.), etc.

[0147] Examples of the above lanthanide metal halides may include YbF, YbF2, YbF3, SmF3, YbCl, YbCl2, YbCl3SmCl3, YbBr, YbBr2, YbBr3SmBr3, YbI, YbI2, YbI3, SmI3, etc.

[0148] Examples of the metalloid halides mentioned above may include antimony halides (e.g., SbCl5, etc.).

[0149] Examples of the above metal tellurides include alkali metal tellurides (e.g., Li2Te, Na2Te, K2Te, Rb2Te, Cs2Te, etc.), alkaline earth metal tellurides (e.g., BeTe, MgTe, CaTe, SrTe, BaTe, etc.), transition metal tellurides (e.g., 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.), post-transition metal tellurides (e.g., ZnTe, etc.), and lanthanide metal tellurides (e.g., LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, It may include TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, etc.

[0150] [Emitting layer in the middle layer (130)]

[0151] When the light-emitting element (10) is a full-color light-emitting element, the light-emitting layer may be patterned into a red light-emitting layer, a green light-emitting layer, and / or a blue light-emitting layer for each individual subpixel. Alternatively, the light-emitting layer may have a structure in which two or more layers among the red light-emitting layer, the green light-emitting layer, and the blue light-emitting layer are stacked in contact or spaced apart, or may have a structure in which two or more materials among the red light-emitting material, the green light-emitting material, and the blue light-emitting material are mixed without layer separation, thereby emitting white light.

[0152] The light-emitting layer may include a host and a dopant. The dopant may include a phosphorescent dopant, a fluorescent dopant, or any combination thereof.

[0153] The content of the dopant in the above-mentioned light-emitting layer may be about 0.01 to about 15 parts by weight per 100 parts by weight of the host.

[0154] Alternatively, the light-emitting layer may include quantum dots.

[0155] Meanwhile, the light-emitting layer may include a delayed fluorescent material. The delayed fluorescent material may act as a host or dopant in the light-emitting layer.

[0156] The thickness of the light-emitting layer may be about 100 Å to about 1000 Å, for example, about 200 Å to about 600 Å. When the thickness of the light-emitting layer satisfies the range described above, excellent light-emitting characteristics can be exhibited without a substantial increase in driving voltage.

[0157] [Host]

[0158] The hole-transporting host may include a compound represented by the following chemical formula 301-1, a compound represented by the following chemical formula 301-2, or any combination thereof:

[0159] <Chemical Formula 301-1>

[0160]

[0161] <Chemical Formula 301-2>

[0162]

[0163] Among the above chemical formulas 301-1 to 301-2,

[0164] Ring A 301 inner ring A 304 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0165] X 301 is O, S, N-[(L 304 ) xb4 -R 304 ], C(R 304 )(R 305 ), or Si(R 304 )(R 305 ) and,

[0166] xb22 and xb23 are independently 0, 1, or 2, and

[0167] L 302 to L 304 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0168] Xb1 to xb4 are independently one of integers 0 to 5, and

[0169] R 301 to R 305 and R 311 to R 314 are independently hydrogen, deuterium, -F, -Cl, -Br, -I, hydroxyl group, cyano group, nitro group, at least one R10a C1-C substituted or unsubstituted 60 alkyl group, at least one R 10a C2-C substituted or unsubstituted 60 alkenyl group, at least one R 10a C2-C substituted or unsubstituted 60 alkynyl group, at least one R 10a C1-C substituted or unsubstituted 60 Alkoxy group, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, at least one R 10a C1-C substituted or unsubstituted 60 Heterocyclic group, -Si(Q 301 )(Q 302 )(Q 303 ), -N(Q 301 )(Q 302 ), -B(Q 301 )(Q 302 ), -C(=O)(Q 301 ), -S(=O)2(Q 301 ), or -P(=O)(Q 301 )(Q 302 ) and,

[0170] Q 301 to Q 303 For a description of each, refer to the description of Q1 in this specification.

[0171] As another example, the host may include an alkaline earth metal complex, a post-transition metal complex, or any combination thereof. For example, the host may include a Be complex, an Mg complex, a Zn complex, or any combination thereof.

[0172] For example, the hole-transporting host may include any one of the following compounds:

[0173]

[0174]

[0175] Meanwhile, the above auxiliary layer may include, for example, the hole transportable host.

[0176] For example, the electron transportable host may include any one of the following compounds:

[0177]

[0178]

[0179] [Phosphorescent Dopant]

[0180] The above phosphorescent dopant may include at least one transition metal as a central metal.

[0181] The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentate ligand, a hexate ligand, or any combination thereof.

[0182] The above phosphorescent dopant may be electrically neutral.

[0183] For example, the phosphorescent dopant may include an organometallic compound represented by the following chemical formula 401:

[0184] <Chemical Formula 401>

[0185] M(L 401 ) xc1 (L 402 ) xc2

[0186] <Chemical Formula 402>

[0187]

[0188] Among the above chemical formulas 401 and 402,

[0189] M is a transition metal (e.g., iridium (Ir), platinum (Pt), palladium (Pd), osmium (Os), titanium (Ti), gold (Au), hafnium (Hf), europium (Eu), terbium (Tb), rhodium (Rh), rhenium (Re), or thulium (Tm)), and

[0190] L 401is a ligand represented by the above chemical formula 402, xc1 is 1, 2, or 3, and if xc1 is 2 or more, 2 or more L 401 They are identical or different from each other,

[0191] L 402 is an organic ligand, xc2 is 0, 1, 2, 3, or 4, and if xc2 is 2 or more, 2 or more L 402 are identical or different from each other,

[0192] X 401 and X 402 are independently nitrogen or carbon, and

[0193] Ring A 401 and ring A 402 are independently of each other, C3-C 60 Carbocyclic group or C1-C 60 It is a heterocyclic group, and

[0194] T 401 is a single bond, -O-, -S-, -C(=O)-, -N(Q 411 )-, -C(Q 411 )(Q 412 )-, -C(Q 411 )=C(Q 412 )-, -C(Q 411 )= or =C= and,

[0195] X 403 and X 404 are independently of each other, chemical bonds (e.g., covalent bonds or coordinate bonds), O, S, N(Q 413 ), B(Q 413 ), P(Q 413 ), C(Q 413 )(Q 414 ) or Si(Q 413 )(Q 414 ) and,

[0196] Above Q 411 to Q 414 For descriptions regarding each, refer to the description of Q1 in this specification, and

[0197] R 401 and R402 are independently hydrogen, deuterium, -F, -Cl, -Br, -I, hydroxyl group, cyano group, nitro group, at least one R 10a C1-C substituted or unsubstituted 20 alkyl group, at least one R 10a C1-C substituted or unsubstituted 20 Alkoxy group, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, at least one R 10a C1-C substituted or unsubstituted 60 Heterocyclic group, -Si(Q 401 )(Q 402 )(Q 403 ), -N(Q 401 )(Q 402 ), -B(Q 401 )(Q 402 ), -C(=O)(Q 401 ), -S(=O)2(Q 401 ) or -P(=O)(Q 401 )(Q 402 ) and,

[0198] Above Q 401 to Q 403 For descriptions regarding each, refer to the description of Q1 in this specification, and

[0199] xc11 and xc12 are independently one of integers from 0 to 10, and

[0200] In the above chemical formula 402, * and *' are each binding sites with M in the above chemical formula 401.

[0201] For example, i) X in the above chemical formula 402 401 is nitrogen, and X 402 is carbon, or ii) X 401 and X 402 All of it can be nitrogen.

[0202] As another example, if xc1 in the above chemical formula 402 is 2 or more, then 2 or more L 401Two of the rings A 401 is optionally, the connector T 402 Connected to each other through, or 2 rings A 402 is optionally, the connector T 403 They can be connected to each other through (see compounds PD1 to PD4 and PD7 below). The above T 402 and T 403 The descriptions for each of T in this specification 401 Refer to the explanation for.

[0203] L in the above chemical formula 401 402 can be any organic ligand. For example, the above L 402 It may include a halogen group, a diketone group (e.g., acetylacetonate group), a carboxylic acid group (e.g., picolinate group), -C (=O), an isonitrile group, a -CN group, a phosphorus group (e.g., phosphine group, phosphite group, etc.), or any combination thereof.

[0204] The above phosphorescent dopant may include, for example, any one of the following compounds:

[0205]

[0206] [Fluorescent Dopants and Delayed Fluorescence Dopants]

[0207] The above-mentioned light-emitting layer may include a fluorescent dopant or a delayed fluorescent material.

[0208] For example, the fluorescent dopant and the delayed fluorescent dopant may include any one of the following compounds:

[0209]

[0210]

[0211] [Quantum Dot]

[0212] The above-mentioned light-emitting layer may include quantum dots.

[0213] In this specification, a quantum dot refers to a crystal of a semiconductor compound and may include any material capable of emitting light of various emission wavelengths depending on the size of the crystal.

[0214] The diameter of the above quantum dots may be, for example, about 1 nm to 10 nm.

[0215] The above quantum dots can be synthesized by a wet chemical process, an organometallic chemical vapor deposition process, a molecular beam epitaxy process, or a similar process.

[0216] The above wet chemical process is a method of growing quantum dot particle crystals after mixing an organic solvent and a precursor material. When the crystals grow, the organic solvent naturally acts as a dispersant coordinated to the surface of the quantum dot crystals and controls the growth of the crystals. Therefore, the growth of quantum dot particles can be controlled through a process that is easier and lower cost than vapor deposition methods such as Metal Organic Chemical Vapor Deposition (MOCVD) or Molecular Beam Epitaxy (MBE).

[0217] The above quantum dots 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.

[0218] Examples of the above-mentioned group II-VI semiconductor compounds include binary compounds such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, etc.; ternary compounds such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, etc.; It may include four-element compounds such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, etc.; or any combination thereof.

[0219] Examples of the above III-V semiconductor compounds may include binary compounds such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, etc.; ternary compounds such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, InPSb, etc.; quaternary compounds such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, etc.; or any combination thereof. Meanwhile, the above III-V semiconductor compounds may further include a group II element. Examples of III-V semiconductor compounds containing additional group II elements may include InZnP, InGaZnP, InAlZnP, etc.

[0220] Examples of the above-mentioned group III-VI semiconductor compounds include binary compounds such as GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2S3, In2Se3, InTe, etc.; InGaS 3 It may include ternary compounds such as InGaSe3, etc.; or any combination thereof.

[0221] Examples of the above-mentioned group I-III-VI semiconductor compounds may include ternary compounds such as AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2, AgAlO2, etc.; or any combination thereof.

[0222] Examples of the above-mentioned group IV-VI semiconductor compounds may include binary compounds such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, etc.; ternary compounds such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, etc.; quaternary compounds such as SnPbSSe, SnPbSeTe, SnPbSTe, etc.; or any combination thereof.

[0223] The above Group IV elements or compounds may include single-element compounds such as Si, Ge, etc.; dual-element compounds such as SiC, SiGe, etc.; or any combination thereof.

[0224] Each element included in the multi-element compounds, such as the above-mentioned binary compounds, ternary compounds, and quaternary compounds, may exist within the particle at a uniform or non-uniform concentration.

[0225] Meanwhile, the above quantum dot may have a single structure in which the concentration of each element contained in the quantum dot is uniform, or a core-shell dual structure. For example, the material contained in the core and the material contained in the shell may be different from each other.

[0226] The shell of the quantum dot can serve as a protective layer to maintain semiconductor properties by preventing chemical degradation of the core and / or as a charging layer to impart electrophoretic properties to the quantum dot. The shell may be a single layer or a multilayer. The interface between the core and the shell may have a concentration gradient in which the concentration of elements present in the shell decreases toward the center.

[0227] Examples of the shell of the above quantum dot include oxides of metals, metalloids, or nonmetals, semiconductor compounds, or combinations thereof. Examples of the oxides of metals, metalloids, or nonmetals may include binary compounds such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, NiO, etc.; ternary compounds such as MgAl2O4, CoFe2O4, NiFe2O4, CoMn2O4, etc.; or any combination thereof. Examples of the above semiconductor compounds may include group II-VI semiconductor compounds; group III-V semiconductor compounds; group III-VI semiconductor compounds; group I-III-VI semiconductor compounds; group IV-VI semiconductor compounds; or any combination thereof, as described in this specification. For example, the semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, or any combination thereof.

[0228] Quantum dots can have a full width of half maximum (FWHM) of the emission wavelength spectrum of about 45 nm or less, specifically about 40 nm or less, and more specifically about 30 nm or less, and color purity or color reproducibility can be improved in this range. In addition, since the light emitted through these quantum dots is emitted in all directions, the wide viewing angle can be improved.

[0229] In addition, the shape of the quantum dots can specifically be spherical, pyramidal, multi-arm, or cubic nanoparticles, nanotubes, nanowires, nanofibers, nanoplate-like particles, etc.

[0230] By controlling the size of the quantum dots, the energy band gap can be controlled, allowing light of various wavelengths to be obtained from the quantum dot light-emitting layer. Therefore, by using quantum dots of different sizes, a light-emitting device that emits light of various wavelengths can be realized. Specifically, the size of the quantum dots can be selected to emit red, green, and / or blue light. Additionally, the size of the quantum dots can be configured to emit white light by combining light of various colors.

[0231] [Electronic transport region in the middle layer (130)]

[0232] The electron transport region may have i) a single-layer structure consisting of a single layer made of a single material, ii) a single-layer structure consisting of a plurality of different materials, or iii) a multilayer structure including a plurality of layers containing a plurality of different materials.

[0233] The above electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

[0234] For example, the electron transport region may have a structure such as an electron transport layer / electron injection layer or a hole blocking layer / electron transport layer / electron injection layer stacked sequentially from the light-emitting layer.

[0235] The electron transport region (e.g., a hole blocking layer or electron transport layer among the electron transport regions) comprises at least one π electron-deficient nitrogen-containing C1-C 60 cyclic group (π electron-deficient nitrogen-containing C1-C 60 It may include metal-free compounds containing a cyclic group.

[0236] For example, the electron transport region may include a compound represented by the following chemical formula 601.

[0237] <Chemical Formula 601>

[0238] [Ar 601 ] xe11 -[(L 601 ) xe1 -R 601 ] xe21

[0239] Among the above chemical formula 601,

[0240] Ar 601 , and L 601 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and

[0241] xe11 is 1, 2, or 3, and

[0242] xe1 is 0, 1, 2, 3, 4, or 5, and

[0243] R 601 is, at least one R 10a C3-C substituted or unsubstituted 60Carbocyclic group, at least one R 10a C1-C substituted or unsubstituted 60 Heterocyclic group, -Si(Q 601 )(Q 602 )(Q 603 ), -C(=O)(Q 601 ), -S(=O)2(Q 601 ), or -P(=O)(Q 601 )(Q 602 ) and,

[0244] Above Q 601 to Q 603 For descriptions regarding each, refer to the description of Q1 in this specification, and

[0245] xe21 is 1, 2, 3, 4, or 5, and

[0246] The above

[0247] Ar 601 , L 601 and R 601 At least one of them is independent of each other, at least one R 10a π electron-deficient nitrogenous C1-C substituted or unsubstituted 60 It could be a click group.

[0248] For example, if xe11 in the above chemical formula 601 is 2 or more, then 2 or more Ar 601 They can be connected to each other through a single bond.

[0249] As another example, Ar in the above chemical formula 601 601 It may be a substituted or unsubstituted anthracene group.

[0250] As another example, the electron transport region may include a compound represented by the following chemical formula 601-1:

[0251] <Chemical Formula 601-1>

[0252]

[0253] In the above chemical formula 601-1,

[0254] X 614is N or C(R 614 ) and, X 615 is N or C(R 615 ) and, X 616 is N or C(R 616 ) and, X 614 To X 616 At least one of them is N, and

[0255] L 611 to L 613 The explanation for each of the above L 601 Refer to the explanation for,

[0256] For descriptions of xe611 to xe613, refer to the description of xe1 above, and

[0257] R 611 to R 613 The explanation for each of the above R 601 Refer to the explanation for,

[0258] R 614 to R 616 They are independently hydrogen, deuterium, -F, -Cl, -Br, -I, hydroxyl group, cyano group, nitro group, C1-C 20 Alkyl group, C1-C 20 Alkoxy group, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It can be a heterocyclic group.

[0259] For example, xe1 and xe611 to xe613 in the above chemical formulas 601 and 601-1 may be 0, 1, or 2 independently of each other.

[0260] The electron transport region is one of the following compounds ET1 to ET45, BCP (2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline), Bphen (4,7-Diphenyl-1,10-phenanthroline) ,It may include Alq3, BAlq, TAZ, NTAZ, or any combination thereof:

[0261]

[0262]

[0263]

[0264]

[0265]

[0266]

[0267]

[0268] The thickness of the electron transport region may be about 100 Å to about 5000 Å, for example, about 160 Å to about 4000 Å. If the electron transport region includes a hole blocking layer, an electron transport layer, or any combination thereof, the thickness of the hole blocking layer or the electron transport layer may be, independently of each other, about 20 Å to about 1000 Å, for example, about 30 Å to about 300 Å, and the thickness of the electron transport layer may be about 100 Å to about 1000 Å, for example, about 150 Å to about 500 Å. When the thickness of the hole blocking layer and / or the electron transport layer satisfies the ranges described above, satisfactory electron transport characteristics can be obtained without a substantial increase in driving voltage.

[0269] The above electron transport region (e.g., the electron transport layer among the electron transport regions) may further include a metal-containing material in addition to the material described above.

[0270] The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. The metal ions of the alkali metal complex may be Li ions, Na ions, K ions, Rb ions, or Cs ions, and the metal ions of the alkaline earth metal complex may be Be ions, Mg ions, Ca ions, Sr ions, or Ba ions. The ligands coordinated to the metal ions of the alkali metal complex and the alkaline earth metal complex may independently include hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.

[0271] For example, the metal-containing material may include a Li complex. The Li complex may include, for example, the following compounds ET-D1 (LiQ) or ET-D2:

[0272]

[0273] The above electron transport region may include an electron injection layer that facilitates electron injection from the second electrode (150). The electron injection layer may be in direct contact with the second electrode (150).

[0274] The electron injection layer may have i) a single-layer structure consisting of a single layer made of a single material, ii) a single-layer structure consisting of a plurality of different materials, or iii) a multilayer structure having a plurality of layers containing a plurality of different materials.

[0275] 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.

[0276] 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.

[0277] The alkali metal-containing compound, alkaline earth metal-containing compound and the rare earth metal-containing compound may include oxides, halides (e.g., fluorides, chlorides, bromides, iodides, etc.), tellurides, or any combination thereof of the alkali metal, alkaline earth metal, and rare earth metal, respectively.

[0278] The above alkali metal-containing compound may include alkali metal oxides such as Li2O, Cs2O, K2O, etc., alkali metal halides such as LiF, NaF, CsF, KF, LiI, NaI, CsI, KI, etc., or any combination thereof. The above alkaline earth metal-containing compound may include BaO, SrO, CaO, Ba x Sr 1-x O(x is 0 <x<1를 만족하는 실수임), Ba x Ca 1-xO(x is 0 <x<1를 만족하는 실수임) 등과 같은 알칼리 토금속 화합물을 포함할 수 있다. 상기 희토류 금속-함유 화합물은, YbF3, ScF3, Sc2O3, Y2O3, Ce2O3, GdF3, TbF3, YbI3, ScI3, TbI3, 또는 이의 임의의 조함을 포함할 수 있다. 또는, 상기 희토류 금속-함유 화합물은, 란타나이드 금속 텔루라이드를 포함할 수 있다. 상기 란타나이드 금속 텔루라이드의 예는, 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, Lu2Te3등을 포함할 수 있다.

[0279] The above alkali metal complex, alkaline earth metal complex, and rare earth metal complex may comprise i) one of the ions of the alkali metal, alkaline earth metal, and rare earth metal as described above, and ii) a ligand bound to the metal ion, for example, hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.

[0280] The electron injection layer described above may consist only of alkali metals, alkaline earth metals, rare earth metals, alkali metal-containing compounds, alkaline earth metal-containing compounds, rare earth metal-containing compounds, alkali metal complexes, alkaline earth metal complexes, rare earth metal complexes, or any combination thereof, or may further include organic materials (e.g., compounds represented by the chemical formula 601).

[0281] According to one embodiment, the electron injection layer may be composed of i) an alkali metal-containing compound (e.g., an alkali metal halide), or ii) a) an alkali metal-containing compound (e.g., an alkali metal halide); and b) an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. For example, the electron injection layer may be a KI:Yb co-deposited layer, an RbI:Yb co-deposited layer, a LiF:Yb co-deposited layer, etc.

[0282] If the electron injection layer further comprises an organic material, the alkali metal, alkaline earth metal, rare earth metal, alkali metal-containing compound, alkaline earth metal-containing compound, rare earth metal-containing compound, alkali metal complex, alkaline earth metal complex, rare earth metal complex, or any combination thereof may be uniformly or non-uniformly dispersed in a matrix containing the organic material.

[0283] The thickness of the electron injection layer may be about 1 Å to about 100 Å or about 3 Å to about 90 Å. When the thickness of the electron injection layer satisfies the range described above, satisfactory electron injection characteristics can be obtained without a substantial increase in driving voltage.

[0284] [Second electrode (150)]

[0285] A second electrode (150) is disposed on the upper portion of the intermediate layer (130) as described above. The second electrode (150) may be a cathode, which is an electron injection electrode. In this case, a metal, alloy, electrically conductive compound, or any combination thereof having a low work function may be used as the material for the second electrode (150).

[0286] 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 semitransmissive electrode, or a reflective electrode.

[0287] The second electrode (150) may have a single-layer structure or a multi-layer structure having multiple layers.

[0288] [Capping layer]

[0289] A first capping layer may be disposed on the outer side of the first electrode (110), and / or a second capping layer may be disposed on the outer side of the second electrode (150). Specifically, the light-emitting element (10) may have a structure in which the first capping layer, the first electrode (110), the intermediate layer (130), and the second electrode (150) are stacked in order, a structure in which the first electrode (110), the intermediate layer (130), the second electrode (150), and the second capping layer are stacked in order, or a structure in which the first capping layer, the first electrode (110), the intermediate layer (130), the second electrode (150), and the second capping layer are stacked in order.

[0290] Light generated in the light-emitting layer of the intermediate layer (130) of the light-emitting element (10) can be emitted to the outside through the first electrode (110), which is a semi-transparent electrode or a transparent electrode, and the first capping layer, and light generated in the light-emitting layer of the intermediate layer (130) of the light-emitting element (10) can be emitted to the outside through the second electrode (150), which is a semi-transparent electrode or a transparent electrode, and the second capping layer.

[0291] The first capping layer and the second capping layer can serve to improve external light emission efficiency based on the principle of constructive interference. As a result, the light extraction efficiency of the light-emitting element (10) is increased, and the light emission efficiency of the light-emitting element (10) can be improved.

[0292] Each of the first capping layer and the second capping layer may include a material having a refractive index of 1.6 or higher (at 589 nm).

[0293] The first capping layer and the second capping layer may independently be an organic capping layer containing organic material, an inorganic capping layer containing inorganic material, or an organic-inorganic composite capping layer containing organic material and inorganic material.

[0294] At least one of the first capping layer and the second capping layer may independently comprise a carbocyclic compound, a heterocyclic compound, an amine group-containing compound, porphine derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, an alkali metal complex, an alkaline earth metal complex, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may optionally be substituted with a substituent comprising O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. According to one embodiment, at least one of the first capping layer and the second capping layer may independently comprise an amine group-containing compound.

[0295] For example, at least one of the first capping layer and the second capping layer may independently include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof.

[0296] According to another embodiment, at least one of the first capping layer and the second capping layer may independently comprise one of the following compounds CP1 to CP6, β-NPB, or any of the same:

[0297]

[0298]

[0299] [Electronic device]

[0300] The light-emitting element may be included in various electronic devices. For example, an electronic device including the light-emitting element may be a light-emitting device, an authentication device, etc.

[0301] The electronic device (e.g., light-emitting device) may further include, in addition to the light-emitting element, i) a color filter, ii) a color conversion layer, or iii) a color filter and a color conversion layer. The color filter and / or color conversion layer may be disposed in at least one direction of propagation of light emitted from the light-emitting element. For example, the light emitted from the light-emitting element may be blue light. Refer to the description of the light-emitting element above. According to one embodiment, the color conversion layer may include quantum dots. The quantum dots may be, for example, quantum dots as described in this specification.

[0302] The electronic device may include a first substrate. The first substrate may include a plurality of subpixel regions, the color filter may include a plurality of color filter regions corresponding to each of the plurality of subpixel regions, and the color conversion layer may include a plurality of color conversion regions corresponding to each of the plurality of subpixel regions.

[0303] A pixel defining film is placed between the plurality of subpixel regions above to define each subpixel region.

[0304] The above color filter may further include a plurality of color filter regions and a light-blocking pattern disposed between the plurality of color filter regions, and the color conversion layer may further include a plurality of color conversion regions and a light-blocking pattern disposed between the plurality of color conversion regions.

[0305] The plurality of color filter regions (or plurality of color conversion regions) comprises a first region emitting a first color light; a second region emitting a second color light; and / or a third region emitting a third color light, wherein the first color light, the second color light, and / or the third color light may have different maximum emission wavelengths. For example, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. For example, the plurality of color filter regions (or plurality of color conversion regions) may include quantum dots. Specifically, the first region may include red quantum dots, the second region may include green quantum dots, and the third region may not include quantum dots. Refer to the description of quantum dots as provided in this specification. The first region, the second region, and / or the third region may each further include scatterers.

[0306] For example, the light-emitting element may emit a first light, the first region may absorb the first light to emit a first-1 color light, the second region may absorb the first light to emit a second-1 color light, and the third region may absorb the first light to emit a third-1 color light. In this case, the first-1 color light, the second-1 color light, and the third-1 color light may have different maximum emission wavelengths. Specifically, the first light may be blue light, the first-1 color light may be red light, the second-1 color light may be green light, and the third-1 color light may be blue light.

[0307] The above electronic device may further include a thin-film transistor in addition to the light-emitting element described above. The thin-film transistor may include a source electrode, a drain electrode, and an active layer, and either one of the source electrode and the drain electrode may be electrically connected to either one of the first electrode and the second electrode of the light-emitting element.

[0308] The above thin-film transistor may further include a gate electrode, a gate insulating film, etc.

[0309] The above active layer may include crystalline silicon, amorphous silicon, organic semiconductor, oxide semiconductor, etc.

[0310] The electronic device may further include a sealing portion for sealing a light-emitting element. The sealing portion may be disposed between the color filter and / or color conversion layer and the light-emitting element. The sealing portion allows light from the light-emitting element to be emitted to the outside while simultaneously blocking external air and moisture from penetrating the light-emitting element. The sealing portion may be a sealing substrate comprising a transparent glass substrate or a plastic substrate. The sealing portion may be a thin film encapsulation layer comprising one or more organic and / or inorganic layers. If the sealing portion is a thin film encapsulation layer, the electronic device may be flexible.

[0311] On the sealing portion, in addition to the color filter and / or color conversion layer, various functional layers may be additionally disposed depending on the application of the electronic device. Examples of the functional layers may include a touchscreen layer, a polarizing layer, etc. The touchscreen layer may be a pressure-sensitive touchscreen layer, a capacitive touchscreen layer, or an infrared touchscreen layer.

[0312] The above authentication device may be a biometric authentication device that authenticates an individual using biometric information (e.g., fingertip, pupil, etc.).

[0313] The above authentication device may further include means for collecting biometric information in addition to the light-emitting element as described above.

[0314] The above electronic device can be applied to various displays, light sources, lighting, personal computers (e.g., mobile personal computers), mobile phones, digital cameras, electronic notebooks, electronic dictionaries, electronic game consoles, medical devices (e.g., electronic thermometers, blood pressure monitors, blood glucose meters, pulse measuring devices, pulse wave measuring devices, electrocardiogram display devices, ultrasound diagnostic devices, endoscope display devices), fish finders, various measuring instruments, instruments (e.g., instruments for vehicles, aircraft, and ships), projectors, etc.

[0315] [Explanation of Figs. 2 and 3]

[0316] FIG. 2 is a cross-sectional view of an electronic device according to one embodiment of the present invention.

[0317] The electronic device of FIG. 2 includes a substrate (100), a thin-film transistor (TFT), a light-emitting element, and a sealing portion (300) that seals the light-emitting element.

[0318] The substrate (100) may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer (210) may be disposed on the substrate (100). The buffer layer (210) may prevent the penetration of impurities through the substrate (100) and may serve to provide a flat surface on the upper surface of the substrate (100).

[0319] A thin-film transistor (TFT) may be disposed on the buffer layer (210). The thin-film transistor (TFT) may include an active layer (220), a gate electrode (240), a source electrode (260), and a drain electrode (270).

[0320] The active layer (220) may include an inorganic semiconductor, an organic semiconductor, or an oxide semiconductor such as silicon or polysilicon, and includes a source region, a drain region, and a channel region.

[0321] A gate insulating film (230) for insulating the active layer (220) and the gate electrode (240) may be disposed on the upper part of the active layer (220), and a gate electrode (240) may be disposed on the upper part of the gate insulating film (230).

[0322] An interlayer insulating film (250) may be disposed on the upper portion of the gate electrode (240). The interlayer insulating film (250) is disposed between the gate electrode (240) and the source electrode (260) and between the gate electrode (240) and the drain electrode (270) to insulate them.

[0323] A source electrode (260) and a drain electrode (270) may be disposed on the interlayer insulating film (250). The interlayer insulating film (250) and the gate insulating film (230) may be formed so as to expose the source region and the drain region of the active layer (220), and the source electrode (260) and the drain electrode (270) may be disposed to be in contact with the exposed source region and the drain region of the active layer (220).

[0324] Such a thin-film transistor (TFT) can be electrically connected to a light-emitting element to drive the light-emitting element 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 a combination thereof. A light-emitting element is provided on the passivation layer (280). The light-emitting element includes a first electrode (110), an intermediate layer (130), and a second electrode (150).

[0325] The first electrode (110) may be disposed on the passivation layer (280). The passivation layer (280) may be disposed so as to expose a certain area without covering the entire drain electrode (270), and the first electrode (110) may be disposed to be connected to the exposed drain electrode (270).

[0326] A pixel defining film (290) including an insulating material may be disposed on the first electrode (110). The pixel defining film (290) exposes a predetermined area of ​​the first electrode (110), and an intermediate layer (130) may be formed in the exposed area. The pixel defining film (290) may be a polyimide or polyacrylic-based organic film. Although not shown in FIG. 2, some or more layers of the intermediate layer (130) may extend to the upper part of the pixel defining film (290) and be disposed in the form of a common layer.

[0327] A second electrode (150) is disposed on the intermediate layer (130), and a capping layer (170) may be additionally formed on the second electrode (150). The capping layer (170) may be formed to cover the second electrode (150).

[0328] A sealing portion (300) may be disposed on the capping layer (170). The sealing portion (300) may be disposed on a light-emitting element and serve to protect the light-emitting element from moisture or oxygen. The sealing portion (300) may include an inorganic film comprising silicon nitride (SiNx), silicon oxide (SiOx), indium tin oxide, indium zinc oxide, or any combination thereof; an organic film comprising polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an acrylic resin (e.g., polymethyl methacrylate, polyacrylic acid, etc.), an epoxy resin (e.g., AGE (aliphatic glycidyl ether), etc.) or any combination thereof; or a combination of an inorganic film and an organic film.

[0329] FIG. 3 is a cross-sectional view of an electronic device according to another embodiment of the present invention.

[0330] The electronic device of FIG. 3 is the same electronic device as the light-emitting device of FIG. 2, except that a light-blocking pattern (500) and a functional area (400) are additionally disposed on the upper part of the encapsulation portion (300). The functional area (400) may be i) a color filter area, ii) a color conversion area, or iii) a combination of a color filter area and a color conversion area. According to one embodiment, the light-emitting element included in the electronic device of FIG. 3 may be a tandem light-emitting element.

[0331] [Manufacturing Method]

[0332] Each layer included in the hole transport region, each light-emitting layer, and each layer included in the electron transport region can be formed in a predetermined region using various methods such as vacuum deposition, spin coating, casting, LB method (Langmuir-Blodgett), inkjet printing, laser printing, and laser thermal imaging (LITI).

[0333] When each layer included in the hole transport region, the emissive layer, and each layer included in the electron transport region are formed by vacuum deposition, the deposition conditions are, for example, a deposition temperature of about 100 to about 500°C, and about 10 -8 to about 10 -3 Within a vacuum level of torr and a deposition rate range of about 0.01 to about 100 Å / sec, the material to be included in the layer to be formed and the structure of the layer to be formed can be selected.

[0334] When forming each layer included in the hole transport region, the light-emitting layer, and each layer included in the electron transport region by spin coating, the coating conditions can be selected, for example, within a coating speed of about 2000 rpm to about 5000 rpm and a heat treatment temperature range of about 80°C to 200°C, taking into consideration the material to be included in the layer to be formed and the structure of the layer to be formed.

[0335] [Definition of Terms]

[0336] C3-C in this specification 60 A carbocyclic group refers to a cyclic group having 3 to 60 carbon atoms, consisting solely of carbon as ring-forming atoms, and C1-C 60 A heterocyclic group refers to a cyclic group having 1 to 60 carbon atoms that includes, in addition to carbon, a heteroatom as a ring-forming atom. The above C3-C 60 Carbocyclic group and C1-C 60 Each heterocyclic group may be a monocyclic group consisting of one ring or a polycyclic group in which two or more rings are condensed together. For example, the above C1-C 60 The number of ring-forming atoms in a heterocyclic group can be 3 to 61.

[0337] In this specification, the cyclic group is the above C3-C 60 Carbocyclic group and C1-C 60 Includes all heterocyclic groups.

[0338] In this specification, π electron-excess C3-C 60 Cyclic group (electron-rich C3-C 60 A cyclic group refers to a cyclic group having 3 to 60 carbon atoms that does not contain *-N=*' as a ring-forming moiety, and π electron-deficient nitrogen-containing C1-C 60 cyclic group (π electron-deficient nitrogen-containing C1-C 60 A cyclic group refers to a heterocyclic group having 1 to 60 carbon atoms containing *-N=*' as a ring-forming moiety.

[0339] for example,

[0340] The above C3-C 60The carbocyclic group may be i) group T1 or ii) a condensed ring group formed by the condensation of two or more groups T1 (e.g., cyclopentadiene group, adamantane group, norbornane group, benzene group, pentylene group, naphthalene group, azulene group, indacene group, acenaphtylene group, phenalene group, phenanthrene group, anthracene group, fluoranthene group, triphenylene group, pyrene group, chrysene group, perylene group, pentapene group, heptylene group, naphthacene group, fisene group, hexacene group, pentacene group, rubicene group, coronene group, ovalene group, indene group, fluorene group, spiro-bifluorene group, benzofluorene group, indenophenanthrene group, or indenoanthracene group), and

[0341] The above C1-C 60A heterocyclic group is i) group T2, ii) a condensed ring group formed by the condensation of two or more groups T2, or iii) a condensed ring group formed by the condensation of one or more groups T2 and one or more groups T1 (e.g., pyrrole group, thiophene group, furan group, indole group, benzodole group, naphthoyndole group, isodole group, benzisoindole group, naphthoyisoindole group, benzocillol group, benzothiophene group, benzofuran group, carbazole group, dibenzocillol group, dibenzothiophene group, dibenzofuran group, indenocarbazole group, indolocarbazole group, benzofurocarbazole group, benzothienocarbazole group, benzocillolocarbazole group, benzodolocarbazole group, benzoindolocarbazole group, benzocarbazole group, benzonaphthofuran group, benzonaphthiophene group, Benzonaphthosilol group, benzofurodibenzofuran group, benzofurodibenzothiophen group, benzothienodibenzothiophen group, pyrazole group, imidazole group, triazole group, oxazole group, isoxazole group, oxadiazole group, thiazole group, isothiaazole group, thiadiazole group, benzopyrazole group, benzimidazole group, benzoxazole group, benzisoxazole group, benzothiaazole group, benzisothiazole group, pyridine group, pyrimidine group, pyrazine group, pyridazine group, triazine group, quinoline group, isoquinoline group, benzoquinoline group, benzisoquinoline group, quinoxaline group, benzoquinoxaline group, quinazolin group, benzoquinazolin group, phenanthroline group, sinoline group, phthalazine group, It may be the naftiridine group, imidazopyridine group, imidazopyrimidine group, imidazotriazine group, imidazopyrazine group, imidazopyridazine group, azacarbazole group, azafluoren group, azadibenzocilol group, azadibenzothiophen group, azadibenzofuran group, etc.),

[0342] The above π electron-excess C3-C 60A cyclic group is i) group T1, ii) a condensed ring group formed by condensing two or more groups T1 together, iii) group T3, iv) a condensed ring group formed by condensing two or more groups T3 together, or v) a condensed ring group formed by condensing one or more groups T3 and one or more groups T1 together (e.g., the above C3-C 60 Carbocyclic group, 1H-pyrrole group, Silol group, Borole group, 2H-pyrrole group, 3H-pyrrole group, Thiophene group, Furan group, Indole group, Benzoindole group, Naphthoyindole group, Isoindole group, Benzoisoindole group, Naphthoyisoindole group, Benzocilol group, Benzothiophene group, Benzofuran group, Carbazole group, Dibenzocilol group, Dibenzothiophene group, Dibenzofuran group, Indenocarbazole group, Indolocarbazole group, Benzofurocarbazole group, Benzothienocarbazole group, Benzocilolocarbazole group, Benzoindolocarbazole group, Benzocarbazole group, Benzonaphthofuran group, Benzonaphthothiophene group, Benzonaphtholilol group, Benzofurodibenzofuran group, It may be the benzopurodibenzothiophen group, benzothienodibenzothiophen group, etc.,

[0343] The above π electron-deficient nitrogen-containing C1-C 60A cyclic group is i) group T4, ii) a condensed ring group formed by the condensation of two or more groups T4, iii) a condensed ring group formed by the condensation of one or more groups T4 and one or more groups T1, iv) a condensed ring group formed by the condensation of one or more groups T4 and one or more groups T3, or v) a condensed ring group formed by the condensation of one or more groups T4, one or more groups T1, and one or more groups T3 (e.g., pyrazole group, imidazole group, triazole group, oxazole group, isoxazole group, oxadiazole group, thiazole group, isothiaazole group, thiadiazole group, benzopyrazole group, benzimidazole group, benzoxazole group, benzisoxazole group, benzothiaazole group, benzisothiazole group, pyridine group, pyrimidine group, pyrazine group, pyridazine group, triazine group, quinoline group, It may be the isoquinoline group, benzoquinoline group, benzisoquinoline group, quinoxaline group, benzoquinoxaline group, quinazolin group, benzoquinazolin group, phenanthroline group, sinoline group, phthalazine group, naftiridine group, imidazopyridine group, imidazopyrimidine group, imidazotriazine group, imidazopyrazine group, imidazopyridazine group, azacarbazole group, azafluoren group, azadibenzocilol group, azadibenzothiophen group, azadibenzofuran group, etc.),

[0344] The above group T1 is a cyclopropane group, a cyclobutane group, a cyclopentane group, a cyclohexane group, a cycloheptane group, a cyclooctane group, a cyclobutene group, a cyclopentene group, a cyclopentadiene group, a cyclohexene group, a cyclohexadiene group, a cycloheptene group, an adamantane group, norbornane (or, bicyclo[2.2.1]heptane)) group, norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.1.1]octane group, or a benzene group, and

[0345] The above group T2 is a furan group, a thiophene group, a 1H-pyrrole group, a silol group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazol group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiaazole group, a thiadiazole group, azasilol group, azaborol group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a tetrazine group, a pyrrolidine group, an imidazolidine group, a dihydropyrrole group, a piperidine group, a tetrahydropyridine group, a dihydropyridine group, a hexahydropyrimidine group, a tetrahydropyrimidine group, a dihydropyrimidine group, a piperazine group, a tetrahydropyrazine group, It is a dihydropyrazine group, a tetrahydropyridazine group, or a dihydropyridazine group, and

[0346] The above group T3 is a furan group, a thiophene group, an 1H-pyrrole group, a silol group, or a borole group, and

[0347] The above group T4 may be a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazol group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiaazole group, a thiadiazole group, an azacilol group, an azaborol group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or a tetrazine group.

[0348] In this specification, the cyclic group, C3-C 60 Carbocyclic group, C1-C 60 Heterocyclic group, π electron-excess C3-C 60 Cyclic group or π electron-deficient nitrogenous C1-C 60 The term "cyclic group" may be a group condensed to any cyclic group, a monovalent group, or a polyvalent group (e.g., a divalent group, a trivalent group, a tetravalent group, etc.) depending on the structure of the chemical formula in which the term is used. For example, "benzene group" may be a benzo group, a phenyl group, a phenylene group, etc., which can be easily understood by a person skilled in the art depending on the structure of the chemical formula containing the "benzene group."

[0349] For example, 1 valence C3-C 60 Carbocyclic group and 1 valence C1-C 60 An example of a heterocyclic group is C3-C 10 Cycloalkyl group, C1-C 10 Heterocycloalkyl group, C3-C 10 Cycloalkenyl group, C1-C 10 Heterocycloalkenyl group, C6-C 60 Aryl group, C1-C 60 It may include a heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic heterocondensed polycyclic group, and a divalent C3-C 60 Carbocyclic groups and 2 C1-C 60 An example of a heterocyclic group is C3-C 10 Cycloalkylene group, C1-C 10Heterocycloalkylene group, C3-C 10 Cycloalkenylene group, C1-C 10 Heterocycloalkenylene group, C6-C 60 Aryllene group, C1-C 60 It may include a heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a divalent non-aromatic heterocondensed polycyclic group.

[0350] C1-C in this specification 60 The alkyl group refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, n -Propyl group, isopropyl group, n -butyl group, sec -butyl group, isobutyl group, tert -butyl group, n -Pentyl, tert -Pentyl group, neopentyl group, isopentyl group, sec -pentyl group, 3-pentyl group, sec -Isopentyl group, n - Hexyl group, isohexyl group, sec -hexyl group, tert -hexyl group, n - heptyl group, isoheptyl group, sec -Heptyl group, tert -Heptyl group, n -Octyl group, iso-octyl group, sec -Octyl group, tert -Octyl group, n -Nonilgi, Isononilgi, sec -Playing, tert -Playing, n - Decyl group, isodecyl group, sec -Desil, tert - Includes decyl groups, etc. C1-C in this specification. 60 The alkylene group is the C1-C 60 It refers to a divalent group having the same structure as an alkyl group.

[0351] C2-C in this specification 60 The alkenyl group is C2-C 60It refers to a monovalent hydrocarbon group comprising one or more carbon-carbon double bonds at the middle or terminal of an alkyl group, and specific examples thereof include an ethenyl group, a propenyl group, a butenyl group, etc. In this specification, C2-C 60 The alkenylene group is the above C2-C 60 It refers to a divalent group having the same structure as an alkenyl group.

[0352] C2-C in this specification 60 The alkynyl group is C2-C 60 It refers to a monovalent hydrocarbon group comprising one or more carbon-carbon triple bonds at the middle or terminal of an alkyl group, and specific examples thereof include ethinyl groups, propynyl groups, etc. In this specification, C2-C 60 The alkynylene group is the above C2-C 60 It refers to a divalent group having the same structure as an alkynyl group.

[0353] C1-C in this specification 60 The alkoxy group is -OA 101 (Here, A 101 The above C1-C 60 It refers to a monovalent group having the chemical formula of an alkyl group, and specific examples thereof include a methoxy group, an ethoxy group, an isopropyloxy group, etc.

[0354] C3-C in this specification 10 A cycloalkyl group refers to a monovalent saturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and specific examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, norbornanyl group (or, a bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.1.1]octyl group, etc. In this specification, C3-C 10 The cycloalkylene group is the C3-C above. 10It refers to a divalent group having the same structure as a cycloalkyl group.

[0355] C1-C in this specification 10 A heterocycloalkyl group refers to a monovalent cyclic group having 1 to 10 carbon atoms, comprising at least one heteroatom as a ring-forming atom in addition to a carbon atom, and specific examples thereof include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, a tetrahydrothiophenyl group, etc. In this specification, C1-C 10 The heterocycloalkylene group is the C1-C 10 It refers to a divalent group having the same structure as a heterocycloalkyl group.

[0356] C3-C in this specification 10 A cycloalkenyl group refers to a monovalent cyclic group having 3 to 10 carbon atoms, having at least one carbon-carbon double bond within the ring, but not having aromaticity; specific examples thereof include cyclopentenyl groups, cyclohexenyl groups, cycloheptenyl groups, etc. In this specification, C3-C 10 The cycloalkenylene group is the above C3-C 10 It refers to a divalent group having the same structure as a cycloalkenyl group.

[0357] C1-C in this specification 10 The heterocycloalkenyl group is a monovalent cyclic group having 1 to 10 carbon atoms, comprising, in addition to the carbon atom, at least one heteroatom as a ring-forming atom, and has at least one double bond within the ring. The C1-C 10 Specific examples of heterocycloalkenyl groups include 4,5-dihydro-1,2,3,4-oxatriazoleyl groups, 2,3-dihydrofuranyl groups, 2,3-dihydrothiophenyl groups, etc. In this specification, C1-C 10 The heterocycloalkenylene group is the above C1-C 10It refers to a divalent group having the same structure as a heterocycloalkenyl group.

[0358] C6-C in this specification 60 An aryl group refers to a monovalent group having a carbocyclic aromatic system with 6 to 60 carbon atoms, and C6-C 60 An arylene group refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. The above C6-C 60 Specific examples of aryl groups include phenyl group, pentalenyl group, naphthyl group, azulenyl group, indacenyl group, acenaphthyl group, phenalenyl group, phenanthrenyl group, anthracenyl group, fluoranthenyl group, triphenylenyl group, pyrenyl group, chrysenyl group, perylenyl group, pentaphenyl group, Includes hepthalenyl group, naphthacenyl group, fisenyl group, hexacenyl group, penthacenyl group, rubisenyl group, coronenyl group, ovalenyl group, etc. The above C6-C 60 Aryl group and C6-C 60 If the arylene group contains two or more rings, the two or more rings can be condensed together.

[0359] C1-C in this specification 60 A heteroaryl group refers to a monovalent group having a heterocyclic aromatic system having 1 to 60 carbon atoms, comprising at least one heteroatom as a ring-forming atom in addition to a carbon atom, and C1-C 60 A heteroarylene group refers to a divalent group having a heterocyclic aromatic system having 1 to 60 carbon atoms, which additionally includes at least one heteroatom as a ring-forming atom in addition to the carbon atoms. 60 Specific examples of heteroaryl groups include pyridinyl groups, pyrimidinyl groups, pyrazinyl groups, pyridazinyl groups, triazinyl groups, quinolinyl groups, benzoquinolinyl groups, isoquinolinyl groups, benzisoquinolinyl groups, quinoxalinyl groups, benzoquinoxalinyl groups, quinazolinyl groups, benzoquinazolinyl groups, cinolinyl groups, phenanthrolinyl groups, phthalazinyl groups, naphthalidinyl groups, etc. The above C1-C60 heteroaryl group and C1-C 60 When a heteroarylene group contains two or more rings, the two or more rings can be condensed together.

[0360] In this specification, a monovalent non-aromatic condensed polycyclic group refers to a monovalent group (e.g., having 8 to 60 carbon atoms) in which two or more rings are condensed together, and the entire molecule contains only carbon as a ring-forming atom and has non-aromaticity. Specific examples of the monovalent non-aromatic condensed polycyclic group include indenyl groups, fluorenyl groups, spiro-bifluorenyl groups, benzofluorenyl groups, indenopenantrenyl groups, indenoanthracenyl groups, etc. In this specification, a divalent non-aromatic condensed polycyclic group refers to a divalent group having the same structure as the monovalent non-aromatic condensed polycyclic group.

[0361] In this specification, a monovalent non-aromatic condensed heteropolycyclic group means a monovalent group (e.g., having 1 to 60 carbon atoms) in which two or more rings are condensed together, and in addition to carbon atoms as ring-forming atoms, at least one heteroatom is included, and the entire molecule is non-aromatic. Specific examples of the above monovalent non-aromatic heterocondensed polycyclic group include: a pyrrole group, a thiophenyl group, a furanyl group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzocylol group, a benzothiophenyl group, a benzofuranyl group, a carbazole group, a dibenzocylol group, a dibenzothiophenyl group, a dibenzofuranyl group, azacarbazole group, azafluorenyl group, azadibenzocylol group, azadibenzothiophenyl group, azadibenzofuranyl group, a pyrazol group, an imidazole group, a triazole group, a tetrazole group, an oxazole group, an isooxazole group, a thiazole group, an isothiazole group, an oxadiazole group, a thiadiazole group, a thiadiazole group, Includes benzopyrazol group, benzimidazole group, benzoxazole group, benzothiazole group, benzoxadiazole group, benzothiadiazole group, imidazopyridinyl group, imidazopyrimidinyl group, imidazotriazinyl group, imidazopyrazinyl group, imidazopyridazinyl group, indenocarbazole group, indolocarbazole group, benzofurocarbazole group, benzothienocarbazole group, benzosilolocarbazole group, benzindolocarbazole group, benzocarbazole group, benzonaphthofuranyl group, benzonaphthothiophenyl group, benzonaphthosilol group, benzofurodibenzofuranyl group, benzofurodibenzothiophenyl group, benzothienodibenzothiophenyl group, etc. In this specification, a divalent non-aromatic heterocondensed polycyclic group refers to a divalent group having the same structure as the monovalent non-aromatic heterocondensed polycyclic group.

[0362] C6-C in this specification 60 The aryloxy group is -OA 102 (Here, A 102 is the above C6-C 60 Pointing to arylgime), and the above C6-C 60arylthio is -SA 103 (Here, A 103 The above C6-C 60 It refers to Arilgiim).

[0363] C7-C in this specification 60 The arylalkyl group is -A 104 A 105 (Here, A 104 is C1-C 54 It is an alkylene group, and A 105 is C6-C 59 Referring to arylgiim), and C2-C in this specification 60 The heteroarylalkyl group is -A 106 A 107 (Here, A 106 C1-C 59 It is an alkylene group, and A 107 C1-C 59 It refers to a heteroaryl group.

[0364] "R" in this specification 10a "Is,

[0365] Deuterium (-D), -F, -Cl, -Br, -I, hydroxyl group, cyano group, or nitro group;

[0366] Deuterium, -F, -Cl, -Br, -I, hydroxyl group, cyano group, nitro group, C3-C 60 Carbocyclic group, C1-C 60 Heterocyclic group, C6-C 60 aryloxy group, C6-C 60 Arylthio group, C7-C 60 Arylalkyl group, C2-C 60 Heteroarylalkyl group, -Si(Q 11 )(Q 12 )(Q 13 ), -N(Q 11 )(Q 12 ), -B(Q 11 )(Q 12 ), -C(=O)(Q 11 ), -S(=O)2(Q 11 ), -P(=O)(Q 11 )(Q 12), or substituted or unsubstituted with any combination thereof, C1-C 60 Alkyl group, C2-C 60 alkenyl group, C2-C 60 alkynyl group, or C1-C 60 Alkoxygenation;

[0367] Deuterium, -F, -Cl, -Br, -I, hydroxyl group, cyano group, nitro group, C1-C 60 Alkyl group, C2-C 60 alkenyl group, C2-C 60 alkynyl group, C1-C 60 Alkoxy group, C3-C 60 Carbocyclic group, C1-C 60 Heterocyclic group, C6-C 60 aryloxy group, C6-C 60 Arylthio group, C7-C 60 Arylalkyl group, C2-C 60 Heteroarylalkyl group, -Si(Q 21 )(Q 22 )(Q 23 ), -N(Q 21 )(Q 22 ), -B(Q 21 )(Q 22 ), -C(=O)(Q 21 ), -S(=O)2(Q 21 ), -P(=O)(Q 21 )(Q 22 ), or substituted or unsubstituted with any combination thereof, C3-C 60 Carbocyclic group, C1-C 60 Heterocyclic group, C6-C 60 aryloxy group, C6-C 60 Arylthio group, C7-C 60 Arylalkyl group, or C2-C 60 heteroarylalkyl group; or

[0368] -Si(Q 31 )(Q 32 )(Q 33 ), -N(Q 31 )(Q 32 ), -B(Q 31 )(Q 32 ), -C(=O)(Q31 ), -S(=O)2(Q 31 ), or -P(=O)(Q 31 )(Q 32 );

[0369] It could be.

[0370] Q1 to Q3, Q in this specification 11 to Q 13 , Q 21 to Q 23 and Q 31 to Q 33 They are independently hydrogen; deuterium; -F; -Cl; -Br; -I; hydroxyl group; cyano group; nitro group; C1-C 60 Alkyl group; C2-C 60 Alkenyl group; C2-C 60 alkynyl group; C1-C 60 Alkoxygen; or,

[0371] Deuterium, -F, cyano group, C1-C 60 Alkyl group, C1-C 60 C3-C substituted or unsubstituted with an alkoxy group, a phenyl group, a biphenyl group, or any combination thereof 60 Carbocyclic group; C1-C 60 Heterocyclic group; C7-C 60 Arylalkyl group; or C2-C 60 It may be a heteroarylalkyl group.

[0372] In this specification, a heteroatom refers to any atom other than a carbon atom. Examples of such heteroatoms include O, S, N, P, Si, B, Ge, Se, or any combination thereof.

[0373] In this specification, third-row transition metals include hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), or gold (Au), etc.

[0374] In this specification, "Ph" means a phenyl group, "Me" means a methyl group, "Et" means an ethyl group, and "ter-Bu" or "Bu t " represents the tert-butyl group, and "OMe" represents the methoxy group.

[0375] In this specification, "biphenyl group" means "phenyl group substituted with a phenyl group." The "biphenyl group" is a substituent of "C6-C 60 It belongs to the "substituted phenyl group" which is an "aryl group".

[0376] In this specification, "terphenyl group" means "phenyl group substituted with a biphenyl group." The "terphenyl group" is a substituent of "C6-C 60 C6-C substituted with aryl groups 60 It belongs to the "substituted phenyl group" which is an "aryl group".

[0377] In this specification, * and *' refer to bonding sites with neighboring atoms in the corresponding chemical formula or moiety, unless otherwise defined.

[0378] Hereinafter, a compound and a light-emitting element according to one embodiment of the present invention will be described in more detail with reference to examples.

[0379] [Example]

[0380] fabrication of light-emitting devices

[0381] Comparative Example 1

[0382] ITO 300Å / Ag 50Å / ITO 300Å (anode) was cut into pieces measuring 50mm x 50mm x 0.7mm, ultrasonically cleaned for 5 minutes each using isopropyl alcohol and pure water, then cleaned by irradiating with ultraviolet light for 30 minutes and exposing to ozone, and the glass substrate was installed in a vacuum deposition apparatus.

[0383] As a hole injection layer, HAT-CN was vacuum deposited on HT1 with 5 wt% as a p-dopant to a thickness of 5 nm on the upper surface of the above substrate.

[0384] Next, a second hole transport layer was formed by vacuum depositing HT1 to a thickness of 100 nm.

[0385] An auxiliary layer was formed by vacuum depositing compound 1-3 to a thickness of 5 nm on top of the above second hole transport layer.

[0386] A light-emitting layer with a thickness of 30 nm was formed by simultaneously depositing compounds 1-3 as a hole transport host, 2-16 as an electron transport host, and compounds 3-11 and 4-1 as dopants in a weight ratio of 7:3:1:0.1 on the above auxiliary layer.

[0387] A first electron transport layer of ET-1 was deposited on the above-mentioned light-emitting layer with a thickness of 5 nm. A second electron transport layer of ET-2 and Liq was deposited on the above-mentioned first electron transport layer with a thickness of 20 nm in a weight ratio of 5:5.

[0388] An electron injection layer was formed by vacuum depositing Liq to a thickness of 1 nm on the upper part of the second electron transport layer, a cathode was formed by vacuum depositing AgMg [Mg 5 wt%] to a thickness of 10 nm, and a capping layer with a thickness of 70 nm was formed by depositing CPL to fabricate the light-emitting device of Comparative Example 1.

[0389]

[0390] Example 1

[0391] A first hole transport layer, which is the first layer of a multilayer film, is formed by vacuum depositing compound 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane on a hole injection layer to a thickness of 250 Å; a second hole transport layer, which is the second layer of a multilayer film, is formed by vacuum depositing compound HT1 on the first layer to a thickness of 500 Å; a first auxiliary layer, which is the third layer of a multilayer film, is formed by vacuum depositing compound 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane on the second layer to a thickness of 250 Å; a second auxiliary layer, which is the fourth layer of a multilayer film, is formed by vacuum depositing compound HT1 on the third layer to a thickness of 50 Å; and a third auxiliary layer, which is the fifth layer of a multilayer film, is formed by vacuum depositing compound 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane on the fourth layer to a thickness of 50 Å. A light-emitting device was fabricated in an equivalent manner to Comparative Example 1, except that a light-emitting layer was formed on the fifth layer.

[0392] Example 2

[0393] A first hole transport layer, which is the first layer of a multilayer film, is formed by vacuum depositing compound 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane on a hole injection layer to a thickness of 250 Å; a second hole transport layer, which is the second layer of a multilayer film, is formed by vacuum depositing compound HT1 on the first layer to a thickness of 500 Å; a third hole transport layer, which is the third layer of a multilayer film, is formed by vacuum depositing compound 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane on the second layer to a thickness of 250 Å; a first auxiliary layer, which is the fourth layer of a multilayer film, is formed by vacuum depositing compound HT1 on the third layer to a thickness of 30 Å; and a first auxiliary layer, which is the fifth layer of a multilayer film, is formed by vacuum depositing compound 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane on the fourth layer to a thickness of 30 Å. A light-emitting device was fabricated in an equivalent manner to Comparative Example 1, except that a light-emitting layer was formed on the above-mentioned fifth layer.

[0394] The structure, refractive index, and thickness of each layer of the multilayer films of the examples and comparative examples are shown in Table 1 below.

[0395] Number of multilayer layers Multilayer film (thickness Å / refractive index) 1st floor 2nd floor 3rd floor 4th floor 5th floor Example 1 5 First hole transport layer (250 Å / 1.74) Second hole transport layer (500 Å / 1.96) First auxiliary layer (250 Å / 1.74) Second auxiliary layer (50 Å / 1.96) Third auxiliary layer (50 Å / 1.74) Example 2 5 First hole transport layer (250 Å / 1.74) Second hole transport layer (500 Å / 1.96) Third hole transport layer (250 Å / 1.74) First auxiliary layer (30 Å / 1.96) Second auxiliary layer (30 Å / 1.74) Comparative Example 1 2 Second hole transport layer (1000 Å / 1.96) Auxiliary layer (50 Å / 1.79) - - -

[0396] The driving voltage, efficiency, and lifespan of the light-emitting devices fabricated in Examples 1 and 2 and Comparative Example 1 were measured, and the results are shown in Table 2.

[0397] Efficiency and lifespan were measured using a source meter (Keithley Instrument, 2400 series) and a measuring device C9920-2-12 from Hamamatsu Photonics.

[0398] Driving voltage (V) efficiency life Example 1 4.6 110% 110% Example 2 4.5 107% 110% Comparative Example 1 4.6 100% 100%

[0399] From Table 2 above, it can be confirmed that the light-emitting element of the example shows superior efficiency and lifespan results compared to the light-emitting element of the comparative example. Explanation of the symbols

[0400] 10: Light-emitting element 110: First electrode 130: Middle layer 150: Second electrode

Claims

Claim 1 A first electrode; a second electrode facing the first electrode; and an intermediate layer interposed between the first electrode and the second electrode and including a light-emitting layer; wherein the intermediate layer comprises a multilayer film having a five-layer structure in which a first layer, a second layer, a third layer, a fourth layer, and a fifth layer are stacked in order, wherein the multilayer film is formed by alternately stacking layers with different refractive indices, and wherein the first layer, the third layer, and the fifth layer independently comprise a compound represented by the following chemical formula 202, <Chemical Formula 202> In the above chemical formula 202, L 201 to L 204 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and L 205 은, *-O-*', *-S-*', *-N(Q 201 )-*', at least one R 10a C1-C substituted or unsubstituted 20 alkylene group, at least one R 10a C2-C substituted or unsubstituted 20 alkenylene group, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, xa1 to xa4 are independently one of integers 0 to 5, xa5 is one of integers 1 to 10, and R 201 to R 204 and Q 201 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and R 201 and R 202 is optionally a single bond, at least one R 10a A C1-C5 alkylene group substituted or unsubstituted with or at least one R 10a Connected to each other through C2-C5 alkenylene groups substituted or unsubstituted, at least one R 10a C8-C substituted or unsubstituted 60 It can form polycyclic groups, and R 203 and R 204 is optionally a single bond, at least one R 10a A C1-C5 alkylene group substituted or unsubstituted with, or at least one R 10a Connected to each other through C2-C5 alkenylene groups substituted or unsubstituted, at least one R 10a C8-C substituted or unsubstituted 60 A light-emitting device capable of forming a polycyclic group, wherein na1 is an integer from 1 to 4, and wherein the second layer and the fourth layer independently comprise a compound represented by the following chemical formula 201: <Chemical Formula 201> In the above chemical formula 201, L 201 to L 203 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and xa1 to xa3 are independently one of integers 0 to 5, and R 201 to R 203 are independent of each other, at least one R 10a C3-C substituted or unsubstituted 60 Carbocyclic group, or at least one R 10a C1-C substituted or unsubstituted 60 It is a heterocyclic group, and R 201 and R 202 is optionally a single bond, at least one R 10a A C1-C5 alkylene group substituted or unsubstituted with or at least one R 10a Connected to each other through C2-C5 alkenylene groups substituted or unsubstituted, at least one R 10a C8-C substituted or unsubstituted 60 It can form a polycyclic group. Claim 2 A light-emitting device according to claim 1, wherein the multilayer film exists between the first electrode and the light-emitting layer. Claim 3 delete Claim 4 A light-emitting device according to claim 1, wherein the intermediate layer further comprises a hole injection layer, and the multilayer film is in direct contact with the hole injection layer and the light-emitting layer. Claim 5 A light-emitting device according to claim 1, wherein the multilayer film comprises a hole transport layer and an auxiliary layer. Claim 6 delete Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 delete Claim 11 A light-emitting element according to claim 1, wherein the first layer is a first hole transport layer and the second layer is a second hole transport layer, and the third layer is a first auxiliary layer and the fourth layer is a second auxiliary layer and the fifth layer is a third auxiliary layer. Claim 12 A light-emitting element according to claim 11, wherein the refractive indices of the first and fifth layers are each smaller than the refractive indices of the second and fourth layers. Claim 13 A light-emitting element according to claim 1, wherein the first layer is a first hole transport layer, the second layer is a second hole transport layer, and the third layer is a third hole transport layer, and the fourth layer is a first auxiliary layer and the fifth layer is a second auxiliary layer. Claim 14 A light-emitting element according to claim 13, wherein the refractive indices of the first and fifth layers are each smaller than the refractive indices of the second and fourth layers. Claim 15 delete Claim 16 A light-emitting element according to claim 1, wherein the thickness of at least one of the second, third, and fourth layers is thicker than the thickness of the first and fifth layers. Claim 17 A light-emitting device according to claim 1, wherein the light-emitting layer comprises a hole-transporting host, an electron-transporting host, and a dopant. Claim 18 A light-emitting device according to claim 17, wherein the dopant comprises a fluorescent dopant, a delayed fluorescent dopant, a phosphorescent dopant, or any combination thereof. Claim 19 An electronic device including the light-emitting element of claim 1. Claim 20 An electronic device according to claim 19, further comprising a thin-film transistor, wherein the thin-film transistor comprises a source electrode and a drain electrode, and the first electrode of the light-emitting element is electrically connected to at least one of the source electrode and the drain electrode of the thin-film transistor.

Images