# US 2021/0242431 A1 · Light-emitting device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242431 A1 - Document ID: US20210242431A1 - Status: Published application - Kind: A1 - Application number: 17/012,700 - Filed: 2020-09-04 - Published: 2021-08-05 - Earliest claimed: 2020-02-04 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Hojung Syn - Web page: https://patentgrep.com/patent/US20210242431A1 ## CPC - C09K 11/06: containing organic luminescent materials - H10K 50/18: Carrier blocking layers - H10K 85/324: {comprising aluminium, e.g. Alq3} - H10K 85/342: {comprising iridium} - H10K 85/631: {Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine} - H10K 85/6572: {comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole} - C09K 2211/1029: containing one nitrogen atom as the heteroatom - C09K 2211/185: of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd - H10K 50/11: characterised by the electroluminescent [EL] layers - H10K 50/15: Hole transporting layers - H10K 50/16: Electron transporting layers - H10K 50/171: {Electron injection layers} - H10K 2101/10: Triplet emission - H10K 2101/40: Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers - H10K 2102/3026: {Top emission} - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract A light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer disposed between the first electrode and the second electrode and including an emission layer; wherein the interlayer further includes: a layer A including an oxide of an inorganic compound; a layer B adjacent to an upper portion of the layer A and including an oxide of an inorganic compound; and a layer C adjacent to a lower portion of the layer A and including an oxide of an inorganic compound, and relationships between a refractive index a of the layer A, a refractive index b of the layer B, and a refractive index c of the layer C satisfy the Equations (1) and (2) defined herein. ## Claims ### Claim 1 A light-emitting device comprising: a first electrode; a second electrode facing the first electrode; and an interlayer disposed between the first electrode and the second electrode and including an emission layer; wherein the interlayer further comprises: a layer A including an oxide of an inorganic compound; a layer B adjacent to an upper portion of the layer A and including an oxide of an inorganic compound; and a layer C adjacent to a lower portion of the layer A and including an oxide of an inorganic compound, and relationships between a refractive index a of the layer A, a refractive index b of the layer B, and a refractive index c of the layer C satisfy the following Equations (1) and (2): b−a=0.1 to 0.6 (1); and c−a=0.1 to 0.6 (2). ### Claim 2 (depends on 1) The light-emitting device of claim 1, wherein the refractive index a has a value from about 1.4 to about 1.6. ### Claim 3 (depends on 1) The light-emitting device of claim 1, wherein the refractive index b has a value from about 1.5 to about 2.0. ### Claim 4 (depends on 1) The light-emitting device of claim 1, wherein the refractive index c has a value from about 1.5 to about 2.0. ### Claim 5 (depends on 1) The light-emitting device of claim 1, wherein the first electrode is an anode, and the second electrode is a cathode. ### Claim 6 (depends on 1) The light-emitting device of claim 1, wherein the light-emitting device further comprises a capping layer. ### Claim 7 (depends on 1) The light-emitting device of claim 1, wherein the light-emitting device further comprises a capping layer, and the layer A is disposed between the emission layer and the capping layer. ### Claim 8 (depends on 1) The light-emitting device of claim 1, wherein the interlayer comprises i) a capping layer, ii) a hole transport region, including a hole injection layer, disposed between the first electrode and the emission layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, and iii) an electron transport region, including a hole blocking layer, disposed between the emission layer and the second electrode, a buffer layer, an electron transport layer, an electron injection layer, or any combination thereof. ### Claim 9 (depends on 1) The light-emitting device of claim 1, wherein the inorganic compound is Al, Si, In, Ga, Zn, or any combination thereof. ### Claim 10 (depends on 1) The light-emitting device of claim 1, wherein the oxide of an inorganic compound is amorphous. ### Claim 11 (depends on 1) The light-emitting device of claim 1, wherein the oxide of an inorganic compound is Al2O3, SiOx (0≤x≤2), Six(Al2O3)1-x (0.4≤x≤1), an amorphous indium gallium zinc oxide, an amorphous indium zinc oxide, In2O3, or any combination thereof. ### Claim 12 The light-emitting device of 8, wherein the layer B comprises an electron transport layer, and the layer C comprises an emission layer. ### Claim 13 The light-emitting device of 8, wherein the layer B comprises an electron transport layer, and the layer C comprises a buffer layer. ### Claim 14 (depends on 13) The light-emitting device of claim 13, wherein the buffer layer is in contact with an emission layer. ### Claim 15 The light-emitting device of 8, wherein the layer B comprises an electron injection layer, and the layer C comprises an electron transport layer. ### Claim 16 The light-emitting device of 8, wherein the layer B comprises a capping layer, and the layer C comprises an electron injection layer. ### Claim 17 (depends on 1) The light-emitting device of claim 1, wherein the emission layer is configured to emit blue light. ### Claim 18 (depends on 1) The light-emitting device of claim 1, wherein the emission layer includes a phosphorescent dopant. ### Claim 19 (depends on 1) The light-emitting device of claim 1, wherein the light-emitting device is a top-emission-type light-emitting device. ### Claim 20 (depends on 1) An electronic apparatus comprising a thin-film transistor and the light-emitting device of claim 1, wherein the thin-film transistor comprises a source electrode, a drain electrode, an activation layer, and a gate electrode, and the first electrode of the light-emitting device is electrically connected to one of the source electrode and the drain electrode of the thin-film transistor.