Light-emitting devices

Abstract

A light-emitting device is provided, comprising: a first electrode; a first emission portion, which is arranged on the first electrode; a second electrode, which is arranged on the first emission portion; and a capping layer, which is arranged on the second electrode and comprises metal atoms and metal halide compounds, wherein the metal atoms are lanthanide metals, transition metals or post-transition metals, and the metal halide compounds are formed by combining alkali metal atoms with halogen atoms.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2019-0018645, filed on February 18, 2019, which is hereby incorporated by reference in its entirety. Technical Field

[0002] The present disclosure herein relates to a light emitting device and a display device including the same, and more particularly, to a light emitting device including a capping layer including metal atoms and a metal halide compound, and a display device including the same. Background Art

[0003] Development of self-luminous display devices as image display devices is being actively carried out. Unlike liquid crystal display devices, a display device including a self-luminous device is a display device in which holes and electrons injected by a first electrode and a second electrode are recombined in an emission layer and a light-emitting material contained in the emission layer emits light to represent an image to be displayed. On the other hand, various studies are being conducted to improve the light extraction efficiency of the display device. Summary of the invention

[0004] Aspects of embodiments of the present disclosure are directed to a light emitting device that can maintain high reliability under a high temperature and / or high humidity environment, and a display apparatus including the light emitting device.

[0005] Aspects of embodiments of the present disclosure are directed to a light emitting device having high light extraction efficiency, and a display apparatus including the light emitting device.

[0006] Embodiments of the present disclosure provide a light-emitting device, comprising: a first electrode; a first emission portion; a second electrode; and a cap layer. The first emission portion may be disposed on the first electrode. The second electrode may be disposed on the first emission portion. The cap layer may be disposed on the second electrode. The cap layer may include metal atoms and metal halide compounds. The metal atoms may include at least one of lanthanide metals, transition metals, and post-transition metals. The metal halide compound may be formed by combining an alkali metal atom with a halogen atom. The cap layer may not include an organic compound (or may not be an organic layer). The halogen atom may include at least one of Cl, Br, and I. The metal halide compound may include at least one of LiI, NaI, KI, RbI, and CsI. The metal atom and the metal halide compound may be combined with each other to form a ternary compound. The ternary compound may be represented by the following formula 1:

[0007] [Formula 1]

[0008] X n Y m Z q

[0009] In Formula 1 above, X and Y may each independently be an alkali metal, a transition metal or a post-transition metal. Z may be a halogen atom. n, m and q may each independently be an integer of 1 to 5.

[0010] In Formula 1, X may be an alkali metal. Y may be a transition metal or a post-transition metal. n and m may both be 1. q may be 3.

[0011] The cap layer may include KYbI 3 ,YbI 3 ,CsYbI 3 ,NaYbI 3 ,LiYbI 3 , RbSm 3 , CsSmI 3 ,KSmI 3 、NaSmI 3 and LiSmI 3 At least one of .

[0012] The light emitting device may further include an auxiliary cover layer. The auxiliary cover layer may be disposed on the cover layer. The auxiliary cover layer may be different from the cover layer in refractive index. The auxiliary cover layer may include an organic compound (or may be an organic layer), and may not include metal atoms and metal halide compounds. The auxiliary cover layer may include metal atoms and metal halide compounds, and may not include organic compounds (or may not be an organic layer). The light emitting device may further include a thin film encapsulation layer. The thin film encapsulation layer may be directly disposed on the cover layer.

[0013] The first emission portion may include an emission layer. The emission layer may be an organic emission layer including an organic compound. The emission layer may be a quantum dot emission layer including quantum dots.

[0014] The light emitting device may further include a second emission portion. The second emission portion may be disposed between the first emission portion and the second electrode. The first emission portion may include a first hole transport region, a first emission layer, and a first electron transport region. The first emission layer may be disposed on the first hole transport region. The first electron transport region may be disposed on the first emission layer. The second emission portion may include a second hole transport region, a second emission layer, and a second electron transport region. The second emission layer may be disposed on the second hole transport region. The second electron transport region may be disposed on the second emission layer. The cap layer may have a refractive index of 1.4-2.0 in the wavelength range of 280nm-780nm.

[0015] In an embodiment of the present disclosure, the light emitting device may include: a first electrode; a hole transport region; an emission layer; an electron transport region; a second electrode; and a capping layer. The hole transport region may be disposed on the first electrode. The emission layer may be disposed on the hole transport region. The electron transport region may be disposed on the emission layer. The second electrode may be disposed on the electron transport region. The capping layer may be disposed on the second electrode. The capping layer may be formed by (or may include) metal atoms and metal halide compounds. The metal atoms may include at least one of lanthanide metals, transition metals, and post-transition metals. The metal halide compound may be formed by combining an alkali metal atom with a halogen atom. The metal atom may include at least one of Eu, Sm, and Yb. The metal halide compound may be formed by combining an alkali metal atom with an iodine atom.

[0016] In an embodiment of the present disclosure, a display device may include: a thin film transistor; and a light emitting device. The light emitting device may be disposed on the thin film transistor. The light emitting device may include a first electrode, a hole transport region, an emission layer, an electron transport region, a second electrode, and a capping layer. The hole transport region may be disposed on the first electrode. The emission layer may be disposed on the hole transport region. The electron transport region may be disposed on the emission layer. The second electrode may be disposed on the electron transport region. The capping layer may be disposed on the second electrode. The capping layer may include metal atoms and metal halide compounds. The metal atoms may include at least one of lanthanide metals, transition metals, and post-transition metals. The metal halide compound may be formed by combining an alkali metal atom with a halogen atom. The metal atom may include at least one of Eu, Sm, and Yb. The metal halide compound may include at least one of LiI, NaI, KI, RbI, and CsI. The capping layer may include KYbI 3 ,YbI 3 ,CsYbI 3 ,NaYbI 3 ,LiYbI 3 , RbSm 3 , CsSmI 3 ,KSmI 3 、NaSmI 3 and LiSmI 3 At least one of . BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are included to provide a further understanding of the inventive concept, and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate exemplary embodiments of the inventive concept and, together with the description, are used to explain the principles of the inventive concept. In the drawings:

[0018] Figure 1 is a cross-sectional view of a light emitting device according to an embodiment of the present disclosure;

[0019] Figure 2 is a cross-sectional view of a light emitting device according to an embodiment of the present disclosure;

[0020] Figure 3 is a cross-sectional view of a light emitting device according to an embodiment of the present disclosure;

[0021] Figure 4 is a perspective view of a display device (light emitting device) according to an embodiment of the present disclosure;

[0022] Figure 5 is a partial cross-sectional view of a display device according to an embodiment;

[0023] Figure 6 is a partial cross-sectional view of a display device according to an embodiment;

[0024] Figure 7 is a schematic flow chart of a method for manufacturing a light emitting device according to an embodiment; and

[0025] Figure 8 is a graph showing the refractive index of a capping layer according to an embodiment. DETAILED DESCRIPTION

[0026] It will be understood that when an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, the element or layer may be directly on, directly connected to, or directly coupled to the other element or layer, or intervening elements or layers may be present. Conversely, when an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers.

[0027] It will be understood that "configuration B is disposed directly on configuration A" means that no separate adhesive layer and / or adhesive member is disposed between configuration A and configuration B. That is, "disposed directly on" means "in contact with."

[0028] The same reference numerals always represent the same elements. For the purpose of effectively describing the technical contents, the thickness, proportion and size of the elements may be exaggerated.

[0029] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0030] It will be understood that, although the terms first, second, etc. can be used here to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish an element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teaching of the present invention, the first element, component, region, layer or part discussed below can be referred to as the second element, component, region, layer or part.

[0031] For ease of description, spatially relative terms such as "under," "beneath," "below," "above," and "upper" may be used herein to describe the relationship of one element or feature to other elements or features as shown in the drawings. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the drawings.

[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. It will also be understood that, unless clearly defined as such herein, terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense.

[0033] In the specification, it should be understood that the terms "comprise", "include" or "have" are intended to mean that the described features, numbers, steps, operations, elements, parts or their combinations may exist, but do not exclude the possibility of the existence or addition of the described features, numbers, steps, operations, elements, parts or their combinations.

[0034] Hereinafter, exemplary embodiments of the inventive concept will be described in detail with reference to the accompanying drawings.

[0035] Figure 1 is a cross-sectional view of a light emitting device LD1 according to an embodiment of the present disclosure.

[0036] Reference Figure 1 , the light emitting device LD1 according to the embodiment may include: a first electrode EL1; a first emission portion EM1 disposed on the first electrode EL1; a second electrode EL2 disposed on the first emission portion EM1; and a cap layer CPL disposed on the second electrode EL2.

[0037] The cap layer CPL may include metal atoms and metal halide compounds. A detailed description will be described later.

[0038] The first emission portion EM1 may include a first hole transport region HTR1, a first emission layer EML1, and a first electron transport region ETR1.

[0039] The first electrode EL1 has conductivity. The first electrode EL1 may be formed of a metal alloy or a conductive compound. The first electrode EL1 may be an anode. The first electrode EL1 may also be a pixel electrode. The first electrode EL1 may be a transmissive electrode, a transflective electrode or a reflective electrode. When the first electrode EL1 is a transmissive electrode, the first electrode EL1 may include a transparent metal oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO) or indium tin zinc oxide (ITZO). When the first electrode EL1 is a transflective electrode or a reflective electrode, the first electrode EL1 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti or a compound or mixture thereof (e.g., a mixture of Ag and Mg). Alternatively, the first electrode EL1 may have a multilayer structure including: a reflective film or a transflective film formed of the above materials; and a transparent conductive film formed of ITO, IZO, ZnO or ITZO. For example, the first electrode EL1 may have a three-layer structure of ITO / Ag / ITO, but the embodiment is not limited thereto. The thickness of the first electrode EL1 may be about 1000 Å. For example, about

[0040] The first hole transport region HTR1 may be disposed on the first electrode EL1. The first hole transport region HTR1 may include at least one of a hole injection layer HIL, a hole transport layer HTL, a hole buffer layer, and an electron blocking layer.

[0041] The first hole transport region HTR1 may have a structure of: a single layer formed of a single material; a single layer formed of a plurality of different materials; or a multi-layer having a plurality of layers formed of a plurality of different materials.

[0042] The first hole transport region HTR1 may be formed by using various methods such as a vacuum deposition method, a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an inkjet printing method, a laser printing method, and / or a laser induced thermal imaging (LITI) method.

[0043] The material of the first hole transport region HTR1 is not particularly limited, and may include appropriate materials in the art, and may further include a charge generating material to improve conductivity. The charge generating material may be uniformly or non-uniformly dispersed in the first hole transport region HTR1. The charge generating material may be, for example, a p-type dopant.

[0044] The thickness of the first hole transport region HTR1 may be about For example, about The thickness of the hole injection layer HIL may be, for example, about The thickness of the hole transport layer HTL may be about When the thicknesses of the first hole transport region HTR1 , the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer satisfy the described ranges, satisfactory hole transport performance may be obtained without significantly increasing the driving voltage.

[0045] As described, in addition to the hole injection layer HIL and the hole transport layer HTL, the first hole transport region HTR1 may further include at least one of a hole buffer layer and an electron blocking layer. The hole buffer layer may improve luminous efficiency by compensating for the resonance distance according to the wavelength of light emitted from the first emission layer EML1. The material included in the first hole transport region HTR1 may also be used as the material included in the hole buffer layer. The electron blocking layer may be used to prevent electron injection from the first electron transport region ETR1 to the first hole transport region HTR1.

[0046] The first emission layer EML1 may be disposed on the first hole transport region HTR1. The first emission layer EML1 may have, for example, about or about The first emission layer EML1 may have the following structures: a single layer formed of a single material; a single layer formed of a plurality of different materials; or a multilayer having a plurality of layers formed of a plurality of different materials.

[0047] The first emission layer EML1 may be any one of an organic emission layer including an organic compound and a quantum dot emission layer including quantum dots. That is, the light emitting device LD1 may be an organic electroluminescent device including an organic compound in the emission layer or a quantum dot electroluminescent device including quantum dots in the emission layer.

[0048] The first emission layer EML1 in the light emitting device LD1 of the embodiment may include anthracene derivatives, pyrene derivatives, fluoranthene derivatives, Derivatives, dihydrobenzanthracene derivatives and / or triphenylene derivatives. Specifically, the first emission layer EML1 may include anthracene derivatives and / or pyrene derivatives. However, the embodiment is not limited thereto, and the first emission layer EML1 may include appropriate materials in the art without limitation.

[0049] The first emission layer EML1 may include a host material and a dopant material. The first emission layer EML1 may include appropriate materials in the art as the host material and the dopant material.

[0050] In addition, in the light emitting device LD1 of the embodiment, the first emission layer EML1 may include quantum dots.

[0051] The core of the quantum dot may be selected from Group II-Group VI compounds, Group III-Group V compounds, Group IV-Group VI compounds, Group IV elements, Group IV compounds, and combinations thereof.

[0052] The II-VI compound can be selected from the group consisting of: a two-element compound (also referred to as a binary compound) selected from the group consisting of CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, and combinations thereof; a two-element compound (also referred to as a binary compound) selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHg S, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS and combinations thereof (referred to as ternary compounds); and four-element compounds (referred to as quaternary compounds) selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe and combinations thereof.

[0053] The Group III-V compounds can be selected from the group consisting of: a two-element compound selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb and combinations thereof; a three-element compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InNAs, InNSb, InPAs, InPSb and combinations thereof; and a four-element compound selected from the group consisting of GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb and combinations thereof.

[0054] The IV-VI compound can be selected from the group consisting of the following compounds: a binary compound selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe and combinations thereof; a ternary compound selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe and combinations thereof; and a quaternary compound selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe and combinations thereof. The IV group element can be selected from the group consisting of Si, Ge and combinations thereof. The IV group compound can be a binary compound selected from the group consisting of SiC, SiGe and combinations thereof.

[0055] At this time, the two-element compound, the three-element compound or the four-element compound may be present in the particle at a uniform concentration, or may be present in the particle in a state where the concentration distribution is partially divided into different states. Alternatively, the quantum dot may also have a core-shell structure in which one quantum dot surrounds other quantum dots. The interface between the core and the shell may have a concentration gradient in which the concentration of the element present in the shell decreases toward the core.

[0056] In some embodiments, quantum dots may have a core-shell structure including a core containing the described nanocrystals and a shell surrounding the core. The shell of the quantum dot may be used as a protective layer for maintaining semiconductor properties by preventing chemical denaturation of the core (or protecting the core from chemical denaturation), and / or may be used as a charging layer for giving quantum dots electrophoretic properties. The shell may have a single layer or multiple layers. The interface between the core and the shell may have a concentration gradient in which the concentration of the element present in the shell decreases toward the core. The shell of the quantum dot may include, for example, a metal oxide or a non-metal oxide, a semiconductor compound, or a combination thereof.

[0057] For example, the metal oxide or non-metal oxide may include: 2 、Al 2 O 3 、TiO 2 、ZnO、MnO、Mn 2 O 3 , Mn 3 O 4 , CuO, FeO, Fe 2 O 3 , Fe 3 O 4 , CoO, Co 3 O 4 and / or binary compounds such as NiO; and / or MgAl 2 O 4 、CoFe2 O 4 、NiFe 2 O 4 and / or CoMn 2 O 4 The invention may be a three-element compound, but the inventive concept is not limited thereto.

[0058] In addition, the semiconductor compound can be, for example, CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, etc., but the inventive concept is not limited thereto.

[0059] The quantum dots may have a full width at half maximum (FWHM) of an emission wavelength spectrum of about 45 nm or less (preferably about 40 nm or less, more preferably about 30 nm or less), and within the described range, color purity may be increased or color reproducibility may be improved. In addition, the light emitted by the quantum dots is emitted in all directions, thereby increasing the viewing angle of the light.

[0060] In addition, the shape of quantum dots is not limited to the specific shapes commonly used in the art, but more specifically, nanoparticles (having spherical shapes, conical shapes, multi-arm shapes and / or cubic shapes), nanotubes, nanowires, nanofibers and / or nanoplate particles, etc. can be used.

[0061] Quantum dots can adjust the color of emitted light according to the particle size, and thus, quantum dots can have various emission colors such as blue, red and / or green.

[0062] The first electron transport region ETR1 may be disposed on the first emission layer EML1. The first electron transport region ETR1 may include at least one of a hole blocking layer, an electron transport layer ETL, and an electron injection layer EIL, but the embodiment is not limited thereto.

[0063] The first electron transport region ETR1 may have a structure of: a single layer formed of a single material; a single layer formed of a plurality of different materials; or a multilayer having a plurality of layers formed of a plurality of different materials.

[0064] The first electron transport region ETR1 may be formed by using various methods such as a vacuum deposition method, a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an inkjet printing method, a laser printing method, and / or a laser induced thermal imaging (LITI) method.

[0065] When the first electron transport region ETR1 includes the electron transport layer ETL, the first electron transport region ETR1 may include an anthracene-based compound. However, the embodiment is not limited thereto, and the first electron transport region ETR1 may include an appropriate material in the art.

[0066] The thickness of the electron transport layer ETL may be about For example, about When the thickness of the electron transport layer ETL satisfies the described range, satisfactory electron transport performance can be obtained without significantly increasing the driving voltage.

[0067] The thickness of the electron injection layer EIL may be about For example, about When the thickness of the electron injection layer EIL satisfies the described range, satisfactory electron injection performance can be obtained without significantly increasing the driving voltage.

[0068] The first electron transport region ETR1 may include a hole blocking layer as described above. The hole blocking layer may include, for example, at least one of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and 4,7-diphenyl-1,10-phenanthroline (Bphen), but the embodiment is not limited thereto.

[0069] The second electrode EL2 may be disposed on the first electron transport region ETR1. The second electrode EL2 may be a common electrode or a cathode electrode. The second electrode EL2 may be a transmissive electrode, a transflective electrode, or a reflective electrode. When the second electrode EL2 is a transmissive electrode, the second electrode EL2 may be formed of a transparent metal oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or indium tin zinc oxide (ITZO).

[0070] When the second electrode EL2 is a transflective electrode or a reflective electrode, the second electrode EL2 may include Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, or a compound or mixture thereof (e.g., a mixture of Ag and Mg). Alternatively, the second electrode EL2 may be a structure having a plurality of layers, the plurality of layers including: a reflective layer or a transflective layer formed of the described materials; and a transparent conductive layer formed of ITO, IZO, ZnO, ITZO, or the like.

[0071] In some embodiments, the second electrode EL2 may be connected to the auxiliary electrode. When the second electrode EL2 is connected to the auxiliary electrode, the resistance of the second electrode EL2 may be reduced.

[0072] The capping layer CPL may be disposed on the second electrode EL2. The capping layer CPL may be directly disposed on the second electrode EL2.

[0073] The cap layer CPL may include metal atoms and metal halide compounds. The metal atoms may include at least one of lanthanide metals, transition metals, and post-transition metals.

[0074] The lanthanide metal may include at least one of 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) and lutetium (Lu), more specifically, the lanthanide metal may be europium (Eu), samarium (Sm) or ytterbium (Yb).

[0075] Metal halide compounds can be formed by combining an alkali metal atom with a halogen atom. The alkali metal may include at least one of lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs). The halogen atom may be fluorine (F), chlorine (Cl), bromine (Br), or iodine (I).

[0076] For example, the halogen atom may include at least one of chlorine (Cl), bromine (Br) and iodine (I). More specifically, the halogen atom may include iodine (I). Since F has a small atomic radius, it will be difficult to react with the metal atom and form a ternary compound to be described later, and therefore, the halogen atom may preferably be Cl, Br or I.

[0077] For example, the metal halide compound may be formed by combining an alkali metal atom with an iodine atom. Specifically, the metal halide compound may include at least one of LiI, NaI, KI, RbI, and CsI.

[0078] Hereinafter, the metal atom used herein means at least one of lanthanide metals, transition metals and post-transition metals. Hereinafter, the metal halide compound used herein means a compound in which an alkali metal atom is combined with a halogen atom.

[0079] The metal atom and the metal halide compound can be combined with each other to form a ternary compound. The ternary compound can be represented by the following formula 1:

[0080] [Formula 1]

[0081] X n Y m Z q

[0082] In Formula 1, X and Y may each independently be an alkali metal, a transition metal or a post-transition metal, Z may be a halogen atom, and n, m and q may each independently be an integer of 1 to 5.

[0083] In Formula 1, for example, X may be an alkali metal, and Y may be a transition metal or a post-transition metal.

[0084] m and n may be the same as or different from each other. For example, m and n may both be 1, and q may be 3. That is, Formula 1 may be represented by the following Formula 2:

[0085] [Formula 2]

[0086] XYZ 3

[0087] However, the embodiment is not limited thereto, and n, m, and q may each be appropriately selected according to the kinds of X, Y, and Z elements in Formula 1.

[0088] The ternary compound may contain KYbI 3 ,YbI 3 ,CsYbI 3 ,NaYbI 3 ,LiYbI 3 , RbSm 3 , CsSmI 3 ,KSmI 3 、NaSmI 3 and LiSmI 3 Specifically, the ternary compound may be RbYbI 3 .

[0089] The metal atoms and the metal halide compound included in the cap layer CPL may be expressed in the form of a ternary compound. Alternatively, the metal atoms and the metal halide compound may be expressed in the form of a mixture of the metal atoms, the metal halide compound, and the ternary compound.

[0090] The cap layer CPL may not include an organic compound. That is, the cap layer CPL may be formed of only an inorganic material. More specifically, the cap layer CPL may include only metal atoms and metal halide compounds.

[0091] Generally, the cap layer in the light emitting device includes an organic material. When the cap layer is formed by using an organic material, there is a problem that reliability decreases under a high temperature and high humidity environment, and there is also a restriction of high cost. Meanwhile, the light emitting device LD1 according to the embodiment includes a cap layer CPL including an inorganic material. Therefore, the light emitting device LD1 according to the embodiment can maintain high reliability even under a high temperature and high humidity environment, and can also reduce manufacturing cost and process cost (to be described later).

[0092] On the other hand, when light is emitted from the first emission layer EML1 in the light emitting device LD1 according to the embodiment, the degree of refraction or reflection of the light may be different depending on the refractive index of the upper component, and therefore, the light extraction efficiency of the light emitting device LD1 may be different. Therefore, it may be necessary to appropriately adjust the refractive index of the component disposed on the upper portion of the emission layer to improve the light extraction efficiency. For example, when the light emitting device LD1 has a resonant structure, it may be necessary to differently adjust the refractive index of the cap layer CPL according to the resonance distance to improve the light extraction efficiency.

[0093] When the cover layer is formed of an organic material (as is usually the case), it may be difficult to form a cover layer outside the refractive index range of about 1.5-1.7 because the organic material has a small refractive index range. Therefore, since a separate optical layer having a desired refractive index is inserted to improve light extraction efficiency, a thin display device DD ( Figure 4 ) will be difficult.

[0094] On the other hand, the cap layer CPL according to the embodiment includes both metal atoms and metal halide compounds, so that the refractive index of the cap layer CPL may be easily adjusted, and the cap layer CPL having various refractive indices may be formed.

[0095] Metal atoms have a high refractive index, while metal halide compounds have a low refractive index, and therefore, a cap layer CPL having a desired refractive index can be easily formed by adjusting the ratio of metal atoms to metal halide compounds. Specifically, the cap layer CPL of the embodiment can have a refractive index in a wide range of about 1.4-2.0 based on light having a wavelength range of about 380nm-780nm.

[0096] When the capping layer includes only metal atoms, light extraction efficiency may be deteriorated due to the opaque nature of the metal atoms, and thus, it may not be suitable to use metal atoms alone as the capping layer material.

[0097] On the other hand, in the embodiment, the cap layer CPL includes both metal atoms and metal halide compounds, so that the metal atoms can react with the metal halide compounds and form a ternary compound. In the embodiment, although metal atoms are used as the material of the cap layer CPL, the formed ternary compound has a transparent property, so that the light extraction efficiency is not deteriorated.

[0098] The cap layer CPL can have a When the thickness of the cap layer CPL satisfies the described range, light extraction efficiency may be improved while fully protecting the organic compound included in the first emission portion EM1 from high temperature and high humidity.

[0099] The light emitting device LD1 may further include a thin film encapsulation layer TFE disposed on the cover layer CPL. The thin film encapsulation layer TFE may be directly disposed on the cover layer CPL. In some embodiments, an input sensing unit for sensing a user's touch, etc. may also be disposed on the thin film encapsulation layer TFE.

[0100] When the thin film encapsulation layer TFE is directly disposed on the cap layer CPL, light emitted from the first emission layer EML1 passes through the thin film encapsulation layer TFE, thereby deteriorating light extraction efficiency. In addition, in the light emitting device LD1 of the embodiment, the cap layer CPL having a refractive index in an appropriate range can be formed, thereby compensating for optical efficiency degradation.

[0101] Figure 2 is a cross-sectional view of a light emitting device LD2 according to an embodiment of the present disclosure. Figure 3 is a cross-sectional view of a light emitting device LD3 according to an embodiment of the present disclosure. Figure 2 and Figure 3 The configurations of the light emitting devices LD2 and LD3 shown in FIG. Figure 1 The described embodiments may be substantially equally applied to the light emitting device LD1 shown in FIG. 1. Therefore, hereinafter, repeated descriptions of the light emitting device LD2 and the light emitting device LD3 may not be provided.

[0102] Reference Figure 2 The light emitting device LD2 may further include an auxiliary cover layer CPL-C disposed on the cover layer CPL. The auxiliary cover layer CPL-C may have a refractive index different from that of the cover layer CPL. For example, when the cover layer CPL has a refractive index of about 2.0, the auxiliary cover layer CPL-C may have a refractive index of about 1.6.

[0103] Since a plurality of cap layers CPL and auxiliary cap layers CPL-C having different refractive indices are provided, the optical efficiency of the light emitting device LD2 may be improved.

[0104] The auxiliary cap layer CPL-C may include metal atoms and metal halide compounds. For example, the auxiliary cap layer CPL-C may be formed of metal atoms and metal halide compounds. However, the material of the auxiliary cap layer CPL-C is not particularly limited thereto, and may include an appropriate cap layer material in the art.

[0105] For example, the auxiliary cover layer CPL-C may include an organic material (or may be an organic layer). Alternatively, both metal atoms and metal halide compounds may be included in the auxiliary cover layer CPL-C (e.g., the auxiliary cover layer CPL-C is not an organic layer). Alternatively, the auxiliary cover layer CPL-C may include an organic material and include metal atoms and metal halide compounds.

[0106] When the auxiliary cap layer CPL-C is an organic layer including, for example, an organic compound, the auxiliary cap layer CPL-C may include, for example, α-NPD, NPB, TPD, m-MTDATA, Alq 3 , CuPc, N4,N4,N4',N4'-tetrakis(biphenyl-4-yl)biphenyl-4,4'-diamine (TPD15), 4,4',4"-tris(carbazol-9-yl)triphenylamine (TCTA), etc.

[0107] The auxiliary cover layer CPL-C may include a material that is the same as or different from that of the cap layer CPL.

[0108] For example, the auxiliary cover layer CPL-C may contain metal atoms and metal halide compounds that are the same as or different from the materials of the cover layer CPL. When the metal atoms and metal halide compounds contained in the cover layer CPL are the same as those contained in the auxiliary cover layer CPL-C, the ratios of the metal atoms and the metal halide compounds contained in the cover layer CPL and the auxiliary cover layer CPL-C may be different from each other.

[0109] exist Figure 2 In the embodiment, the cap layer CPL and the auxiliary cap layer CPL-C are stacked in two layers, but the embodiment is not limited thereto, and three or more layers may be stacked.

[0110] Reference Figure 3 The light emitting device LD3 may further include a second emission part EM2. The second emission part EM2 may be disposed between the first emission part EM1 and the second electrode EL2.

[0111] The second emission portion EM2 may include a second hole transport region HTR2, a second emission layer EML2, and a second electron transport region ETR2, which are sequentially stacked.

[0112] The described embodiments of the first hole transport region HTR1 , the first emission layer EML1 , and the first electron transport region ETR1 may be substantially identically applied to the second hole transport region HTR2 , the second emission layer EML2 , and the second electron transport region ETR2 , respectively.

[0113] Figure 3 It is shown that the light emitting device LD3 includes two emission parts EM1 and EM2 (or referred to as a first emission part EM1 and a second emission part EM2), but the embodiment is not limited thereto and may also include three or more emission parts.

[0114] Each of the plurality of emission parts EM1 and EM2 may emit light of the same color as each other, or may emit light of different colors from each other. For example, all emission parts EM1 and EM2 may emit blue light. Alternatively, when the light emitting device LD3 includes three emission parts, the three emission parts may emit red light, green light, and blue light, respectively. However, the embodiment is not limited thereto, and each of the emission parts EM1 and EM2 may emit light having various wavelength ranges.

[0115] A plurality of emission parts EM1 and EM2 may be provided in the light emitting device LD1 of the embodiment, thereby improving current efficiency and obtaining a long life of the device.

[0116] The light emitting device LD3 may further include a charge generation layer CGL. The charge generation layer CGL may be disposed between the emission portions EM1 and EM2.

[0117] When a voltage is applied to the charge generation layer CGL, charges may be generated. The charge generation layer CGL may be disposed between the emission parts EM1 and EM2 and may be used to adjust the charge balance between the emission parts EM1 and EM2. For example, the charge generation layer CGL may be used to assist electron injection into the first emission part EM1 and assist hole injection into the second emission part EM2.

[0118] The charge generation layer CGL may be configured as a layer in which an electron injection material and a hole injection material are mixed. Alternatively, the charge generation layer CGL may be configured as two or more layers. For example, the charge generation layer CGL may include an N-type charge generation layer doped with an N-type dopant and a P-type charge generation layer doped with a P-type dopant. The N-type charge generation layer may be directly disposed on or adjacent to the first electron transport region ETR1, and may be used to assist electron injection, and the P-type charge generation layer may be directly disposed on or adjacent to the lower portion of the second hole transport region HTR2, and may be used to assist hole injection.

[0119] The material of the charge generation layer CGL is not particularly limited, and appropriate materials in the art may be used without limitation.

[0120] When the number of emission parts in the light emitting device LD3 is adjusted, the required refractive index of the cap layer CPL is also different. The cap layer CPL of the embodiment can easily adjust the refractive index, thereby easily improving the light extraction efficiency of the light emitting device LD3 including a plurality of emission parts.

[0121] In the following, reference will be made to Figures 4 to 6A display device DD (including a light emitting device) according to an embodiment of the present disclosure is described. In the display device DD, the display device DD-1, and the display device DD-2 of the embodiment, the described device can be substantially equally applied to Figures 1 to 3 The light emitting device LD1, the light emitting device LD2 and the light emitting device LD3 shown in FIG. 1 have the same configuration. Therefore, in the following, reference may not be provided. Figures 1 to 3 Repeated examples described.

[0122] Figure 4 is a perspective view of a display device DD according to an embodiment of the present disclosure.

[0123] The upper surface of each component is parallel to a plane defined by the first directional axis DR1 and the second directional axis DR2. The thickness direction of each component is represented by the third directional axis DR3. The upper side (or upper portion) and the lower side (or lower portion) of each component are separated by the third directional axis DR3. However, the directions represented by the first directional axis DR1, the second directional axis DR2, and the third directional axis DR3 are relative concepts and can be converted into different directions. In the following, the first direction to the third direction refer to the same figure marks in the directions represented by the first directional axis DR1, the second directional axis DR2, and the third directional axis DR3, respectively.

[0124] The display device DD according to the embodiment may include a plurality of pixels PX. The pixels PX may be arranged in a matrix form. Each of the pixels PX may include a light emitting device LD1, a light emitting device LD2, and a light emitting device LD3 according to the description of the embodiment of the present disclosure. At least some of the pixels PX may generate light having different wavelength regions, respectively. However, the embodiment is not limited thereto, and the pixels PX may generate light having the same wavelength region.

[0125] Figure 5 is a partial cross-sectional view of a display device DD-1 according to the embodiment.

[0126] Figure 5 The display device DD-1 shown in the figure can be used with Figure 4 Corresponding to the display device DD shown in .

[0127] Reference Figure 5 The display device DD-1 may include a base substrate BS, a thin film transistor TFT, a plurality of insulating layers, a pixel defining layer PDL and a light emitting device LD1.

[0128] The thin film transistor TFT and the light emitting device LD1 may be stacked on the base substrate BS. The material of the base substrate BS is not particularly limited as long as the material of the base substrate BS is generally used, and the base substrate BS may be formed of an insulating material such as glass, organic polymer, and crystal.

[0129] A base buffer layer may be provided on the base substrate BS. The base buffer layer may be used to prevent impurities from diffusing into the thin film transistor TFT or to protect the thin film transistor TFT from being diffused into the thin film transistor TFT. The base buffer layer may be made of silicon nitride (SiN x ), silicon oxide (SiO x ) or silicon oxynitride (SiO x N y ) etc., and depending on the material and process conditions of the base substrate BS, a base buffer layer may no longer be provided.

[0130] The semiconductor layer SM may be disposed on the base substrate BS. The semiconductor layer SM may be formed of a semiconductor material and may be used as an active layer in the thin film transistor TFT. The semiconductor layer SM may include a source region SA, a drain region DRA, and a channel region CA disposed between the source region SA and the drain region DRA. The semiconductor layer SM may be formed of an inorganic semiconductor or an organic semiconductor. The source region SA and the drain region DRA may be doped with N-type impurities or P-type impurities.

[0131] The gate insulating layer GI may be disposed on the semiconductor layer SM. The gate insulating layer GI may cover the semiconductor layer SM. The gate insulating layer GI may be formed of an organic insulating material or an inorganic insulating material.

[0132] The gate electrode GE may be disposed on the gate insulating layer GI. The gate electrode GE may be formed to cover a region corresponding to the channel area CA of the semiconductor layer SM.

[0133] The interlayer insulating layer IL may be disposed on the gate electrode GE. The interlayer insulating layer IL may cover the gate electrode GE. The interlayer insulating layer IL may be formed of an organic insulating material or an inorganic insulating material.

[0134] The source electrode SE and the drain electrode DE may be disposed on the interlayer insulating layer IL. The drain electrode DE may contact the drain region DRA of the semiconductor layer SM through a first contact hole CH1 formed through the gate insulating layer GI and the interlayer insulating layer IL, and the source electrode SE may contact the source region SA of the semiconductor layer SM through a second contact hole CH2 formed through the gate insulating layer GI and the interlayer insulating layer IL.

[0135] A passivation layer PL may be disposed on the source electrode SE and the drain electrode DE. The passivation layer PL may function as a protective film for protecting the thin film transistor TFT, and may also function as a planarization film for planarizing an upper surface of the thin film transistor TFT.

[0136] The detailed description of the light emitting device LD1 is the same as the above description, and thus, the detailed description thereof may not be provided again.

[0137] The first electrode EL1 may be disposed on the passivation layer PL, and the pixel defining layer PDL may be disposed on the passivation layer PL and the first electrode EL1. The first electrode EL1 may contact the drain electrode DE through the third contact hole CH3 formed through the passivation layer PL. In the pixel defining layer PDL, an opening OH for exposing at least a portion of the upper surface of the first electrode EL1 may be defined. The pixel defining layer PDL may be configured to separate the light emitting device LD1 (or divide the light emitting device LD1) to correspond to each pixel PX. The material of the pixel defining layer PDL is not particularly limited, and appropriate materials in the art may be used without limitation.

[0138] Figure 6 is a partial cross-sectional view of a display device DD-2 according to an embodiment. Figure 6 The display device DD-2 may include a light emitting device LD2. In addition to the light emitting device LD2, the display device DD-2 may include an auxiliary cover layer CPL-C disposed on the cover layer CPL. Figure 5 The description of display device DD-1 applies equally to Figure 6 The display device DD-2 is shown in FIG.

[0139] Reference Figure 5 and Figure 6 In other words, the display device DD of the embodiment may include a light emitting device LD1 having the described single-layer cap layer CPL, and a light emitting device LD2 having the described multi-layer cap layer (cap layer CPL and auxiliary cap layer CPL-C). Although not shown, the display device DD may naturally include a light emitting device LD3 including a plurality of emission portions EM1 and EM2.

[0140] In the following, reference will be made to Figure 7 A method of manufacturing the described light emitting device is described. Figure 7 is a schematic flowchart of a method for manufacturing a light emitting device according to an embodiment.

[0141] Reference Figure 7 , a method for manufacturing a light emitting device LD according to an embodiment of the present disclosure may include: a task S100 for forming a first electrode EL1; a task S200 for forming a first hole transport region HTR1 on the first electrode EL1; a task S300 for forming a first emission layer EML1 on the first hole transport region HTR1; a task S400 for forming a first electron transport region ETR1 on the first emission layer EML1; a task S500 for forming a second electrode EL2 on the first electron transport region ETR1; and a task S600 for forming a capping layer CPL by co-depositing metal atoms and a metal halide compound.

[0142] The task S100 for forming the first electrode EL1, the task S200 for forming the first hole transport region HTR1, the task S300 for forming the first emission layer EML1, the task S400 for forming the first electron transport region ETR1, and the task S500 for forming the second electrode EL2 can be performed by using an appropriate method in the art, respectively. For example, each task can be performed by using a vacuum deposition method. However, the embodiment is not limited thereto, and can also be performed by using a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an inkjet printing method, a laser printing method, and / or a laser induced thermal imaging (LITI) method.

[0143] The task S600 for forming the cap layer CPL may be performed by co-depositing metal atoms and metal halide compounds. However, the embodiment is not limited thereto, and may be performed by mixing the metal atoms and the metal halide compound and then applying the mixture to the second electrode EL2. For example, the task S600 for forming the cap layer CPL may also be performed by mixing the metal atoms and the metal halide compound, first heating to form a ternary compound, and then depositing the ternary compound.

[0144] Task S600 for forming the cap layer CPL may be performed by co-depositing metal atoms and metal halide compounds in a volume ratio of 2:8 to 8:2 (which may also be expressed as a volume ratio of the metal atom component to the metal halide compound component of 2:8 to 8:2). When the ratio of the metal atom component exceeds the described ratio range, the remaining metal atom component (i.e., the remaining metal atoms) will be too high in content and will not be able to react to form a ternary compound (by reacting with the metal halide compound component (i.e., the metal halide compound)). Therefore, the light transmittance of the cap layer CPL will be reduced, and the light extraction efficiency of the cap layer CPL will also be reduced. When the described ratio range is met, the problem will not occur.

[0145] In addition, since the metal atoms and the metal halide compounds of the embodiments have high process stability, the capping layer CPL may be formed by using appropriate equipment generally used in the art.

[0146] The task S600 for forming the cap layer CPL may be performed by co-depositing Yb and RbI. When Yb and RbI are co-deposited, Yb and RbI may react to form a ternary compound RbYbI 3 Since the method for manufacturing the light emitting device LD1 according to the embodiment of the present disclosure includes forming the cap layer CPL using an inorganic material, the light emitting device LD1 maintaining high reliability under a high temperature and high humidity environment can be formed, and the cap layer CPL having a desired refractive index can be produced.

[0147] In an embodiment, since the cap layer CPL has a desired refractive index, it is not necessary to further form a separate optical layer, thereby simplifying the process and reducing the process cost.

[0148] In some embodiments, the method for manufacturing the light emitting device LD1 of the embodiment may further include forming a thin film encapsulation layer TFE directly disposed on the cap layer CPL.

[0149] The method for manufacturing the light emitting device LD2 having multiple cap layers (cap layer CPL and auxiliary cap layer CPL-C) may be substantially the same as the method for manufacturing the light emitting device LD1 having a single cap layer CPL, except that it also includes forming an auxiliary cap layer CPL-C disposed on the cap layer CPL. The task for forming the auxiliary cap layer CPL-C may be substantially the same as the task S600 for forming the cap layer CPL.

[0150] In the following, reference will be made to specific examples and Figure 8 Embodiments of the present disclosure are described in more detail. The following examples are provided for illustrative purposes only, and the scope of the inventive concept is not limited thereto. Figure 8 is a graph showing the refractive index of the cap layer CPL according to the embodiment.

[0151] (Example 1)

[0152] The cap layer according to Example 1 is formed as follows:

[0153] Yb and RbI were co-deposited on the substrate in a volume ratio of 2:1 to form a capping layer.

[0154] (Example 2)

[0155] A cap layer according to Example 2 was formed in the same manner as in Example 1, except that Yb and RbI were co-deposited at a volume ratio of 1:1.

[0156] (Example 3)

[0157] A cap layer according to Example 3 was formed in the same manner as in Example 1, except that Yb and RbI were co-deposited at a volume ratio of 1:2.

[0158] (Example 4)

[0159] A cap layer according to Example 4 was formed in the same manner as in Example 1, except that Yb and RbI were co-deposited at a volume ratio of 1:4.

[0160] The refractive index of the capping layer according to Examples 1 to 4 according to the emission wavelength (ie, the refractive index of each of the capping layers according to Examples 1 to 4 according to the emission wavelength) is measured, and Figure 8 The results are shown in .

[0161] The refractive index in Examples 1 to 4 was measured as follows. The cover layer was irradiated with light having each wavelength in a vacuum state at 25° C. Then, the ratio of the sine function value of the incident angle of the light to the cover layer to the sine function value of the refraction angle of the light to the cover layer was measured.

[0162] Reference Figure 8 , the refractive index of the cap layer can be variously adjusted by adjusting the ratio of Yb to RbI. In contrast, when the cap layer is formed by using an organic material, the refractive index of the cap layer is difficult to deviate from the refractive index range of about 1.5-1.7.

[0163] In the light-emitting devices according to Examples 1 to 4, the ratio of Yb to RbI is adjusted, and Yb and RbI are co-deposited, thereby forming a cap layer having a refractive index range of about 1.4-2.0. Therefore, it is possible to manufacture light-emitting devices having various refractive index ranges required for each display device, and by including the cap layer of the embodiment, a light-emitting device of the embodiment with high light extraction efficiency can be obtained. That is, in the embodiment, by appropriately adjusting the ratio of the metal atomic component to the metal halide compound component in the cap layer CPL (for example, by adjusting the volume ratio of the metal atomic component to the metal halide compound component to 2:8 to 8:2), a cap layer having a desired refractive index can be easily formed.

[0164] The present disclosure provides a light emitting device LD1, a light emitting device LD2, and a light emitting device LD3 including a cap layer CPL containing metal atoms and a metal halide compound. Therefore, the light emitting device LD1, the light emitting device LD2, and the light emitting device LD3 of the embodiment and the display device DD, the display device DD-1, and the display device DD-2 including the light emitting device can maintain high reliability under high temperature and high humidity environments.

[0165] The present disclosure also provides a light emitting device LD1, a light emitting device LD2 and a light emitting device LD3, and a display device DD, a display device DD-1 and a display device DD-2 including the light emitting devices. Since the refractive index of the cover layer CPL is easily adjusted by using metal atoms and metal halide compounds as the material of the cover layer CPL, the light emitting device LD1, the light emitting device LD2 and the light emitting device LD3 have high light extraction efficiency.

[0166] According to the embodiments of the present disclosure, a light emitting device and a display apparatus including the same may maintain high reliability under a high temperature and high humidity environment.

[0167] According to the embodiments of the present disclosure, a light emitting device and a display apparatus including the same may have high light extraction efficiency.

[0168] As used herein, the terms "substantially," "about," and similar terms are used as terms of approximation, rather than terms of degree, and are intended to account for the inherent variations in measurements or calculations that would be recognized by those having ordinary skill in the art.

[0169] In addition, any numerical range stated herein is intended to include all subranges of the same numerical precision contained within the stated range. For example, the range "1.0 to 10.0" is intended to include all subranges between the stated minimum value 1.0 and the stated maximum value 10.0 (and including the stated minimum value 1.0 and the stated maximum value 10.0), that is, having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as, for example, 2.4 to 7.6. Any maximum numerical limit stated herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit stated in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to modify this specification (including claims) to explicitly state any subrange within the range explicitly stated herein.

[0170] As used herein, the term "use" may be considered synonymous with the term "utilize."

[0171] When a statement such as "at least one of..." follows a list of elements, it modifies the entire list of elements, not the individual elements of the list. In addition, when describing embodiments of the inventive concept, the use of "may" means "one or more embodiments of the inventive concept." In addition, the term "exemplary" is intended to mean an example or instance.

[0172] Although exemplary embodiments of the present invention have been described, it is understood that the present invention should not be limited to these exemplary embodiments and that various changes and modifications may be made by one of ordinary skill in the art within the spirit and scope of the present invention as claimed in the claims and its equivalents.

Claims

1. A light emitting device, comprising: a first electrode; A first emitting portion, located on the first electrode; a second electrode, located on the first emitting portion; as well as a capping layer, located on the second electrode and comprising metal atoms and a metal halide compound, wherein the metal atom comprises at least one of a lanthanide metal, a transition metal and a post-transition metal, and the metal halide compound is formed by combining an alkali metal atom with a halogen atom, wherein the metal atoms and the metal halide compound are co-deposited in a volume ratio of 2:8 to 8:2, and the metal atoms and the metal halide compound are combined with each other to form a ternary compound to form the cap layer, and Wherein, the cover layer has a refractive index of 1.4-2.0 in the wavelength range of 280 nm-780 nm.

2. The light emitting device according to claim 1, wherein: The capping layer does not include an organic compound.

3. The light emitting device according to claim 1, wherein: The halogen atom includes at least one of Cl, Br and I.

4. The light emitting device according to claim 1, wherein: The metal halide compound includes at least one of LiI, NaI, KI, RbI, and CsI.

5. The light emitting device according to claim 1, wherein: The ternary compound is represented by the following formula 1: [Formula 1] X n Y m Z q Among them, in formula 1, X and Y are each independently an alkali metal, a transition metal or a post-transition metal, Z is a halogen atom, and n, m and q are each independently an integer from 1 to 5.

6. The light emitting device according to claim 5, in, In formula 1, X is an alkali metal, Y is a transition metal or a post-transition metal, n and m are both 1, and q is 3.

7. The light emitting device according to claim 1, wherein: The ternary compound includes at least one of KYbI3, RbYbI3, CsYbI3, NaYbI3, LiYbI3, RbSmI3, CsSmI3, KSmI3, NaSmI3 and LiSmI3.

8. The light emitting device according to claim 1, further comprising a second emitting portion, in, The first emission portion includes: a first hole transport region; a first emission layer located on the first hole transport region; and a first electron transport region located on the first emission layer, and The second emission portion includes: a second hole transport region; a second emission layer located on the second hole transport region; and a second electron transport region located on the second emission layer.

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