# US 12,004,363 B2 · Light-emitting structure, display panel and display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,004,363 B2 - Document ID: US12004363B2 - Status: Granted - Kind: B2 - Application number: 17/255,569 - Filed: 2020-02-26 - Published: 2021-09-16 - Granted: 2024-06-04 - Earliest claimed: 2019-04-26 - Assignees: Beijing BOE Technology Development Co., Ltd.; Boe Technology Group Co., Ltd. - Applicants: Beijing Boe Technology Development Co., Ltd.; Boe Technology Group Co., Ltd. - Inventors: Dong Li; Wenhai Mei; Boris Kristal - Web page: https://patentgrep.com/patent/US12004363B2 ## CPC - H10K 50/16: Electron transporting layers - C01B 25/087: {of gallium or indium} - C01G 9/006: {Compounds containing zinc, with or without oxygen or hydrogen, and containing two or more other elements} - C09K 11/0883: {Arsenides; Nitrides; Phosphides} - C09K 11/70: containing phosphorus - H10K 50/115: comprising active inorganic nanostructures, e.g. luminescent quantum dots - B82Y 20/00: Nanooptics, e.g. quantum optics or photonic crystals - C01P 2004/64: Nanometer sized, i.e. from 1-100 nanometer - C01P 2006/40: Electric properties - H10K 2101/30: Highest occupied molecular orbital [HOMO], lowest unoccupied molecular orbital [LUMO] or Fermi energy values - H10K 2102/331: {Nanoparticles used in non-emissive layers, e.g. in packaging layer} - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} - C01G: COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts or peroxyacids C01B15/00; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium, or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds containing nitrogen, other non-metals and metal C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanamide C01C3/16; thiocyanates C01C3/20) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS ## Abstract A light-emitting structure, a display panel and a display device. The light-emitting structure comprises a first light-emitting element. The first light-emitting element comprises a first light-emitting layer, a first electron transport layer and a first cathode. The first cathode is in contact with the first electron transport layer. The energy level of conduction band minimum (CBM) of the first electron transport layer is greater than the Fermi level of the first cathode. A difference between the energy level of CBM of the first electron transport layer and the Fermi level of the first cathode is in a range from 0.3 to 0.6 eV. ## Claims ### Claim 1 A light-emitting structure, comprising: a first light-emitting element comprising a first light-emitting layer, a first electron transport layer, and a first cathode, wherein the first cathode is in contact with the first electron transport layer, an energy level of conduction band minimum (CBM) of the first electron transport layer is larger than a Fermi level of the first cathode, and a difference between the energy level of CBM of the first electron transport layer and the Fermi level of the first cathode is in a range from 0.3 to 0.6 eV, the energy level of CBM of the first light-emitting layer is smaller than that of the first electron transport layer, the first electron transport layer comprises ZnMgO nanoparticles, and a molar percentage of Mg in the first electron transport layer is in a range from 10% to 20%. ### Claim 2 (depends on 1) The light-emitting structure according to claim 1, wherein the molar percentage of Mg in the first electron transport layer is in a range from 13% to 16%. ### Claim 3 (depends on 1) The light-emitting structure according to claim 1, wherein a material of the first light-emitting layer comprises a red cadmium-free quantum dot material. ### Claim 4 (depends on 3) The light-emitting structure according to claim 3, wherein the material of the first light-emitting layer comprises indium phosphide. ### Claim 5 (depends on 1) The light-emitting structure according to claim 1, further comprising: a second light-emitting element comprising a second light-emitting layer, a second electron transport layer, and a second cathode, wherein the second cathode is in contact with the second electron transport layer, the energy level of CBM of the first light-emitting layer is smaller than that of the second light-emitting layer, and the energy level of CBM of the first electron transport layer is larger than that of the second electron transport layer. ### Claim 6 (depends on 5) The light-emitting structure according to claim 5, wherein a potential barrier of electrons from the first cathode to the first electron transport layer is larger than a potential barrier of electrons from the second cathode to the second electron transport layer. ### Claim 7 (depends on 5) The light-emitting structure according to claim 5, wherein the energy level of CBM of the first light-emitting layer is smaller than that of the first electron transport layer, the energy level of CBM of the second light-emitting layer is larger than that of the second electron transport layer, and the Fermi level of the second cathode is substantially equal to that of the second electron transport layer. ### Claim 8 (depends on 5) The light-emitting structure according to claim 5, wherein the first electron transport layer comprises ZnMgO nanoparticles, the second electron transport layer comprises ZnO nanoparticles or ZnMgO nanoparticles, and a molar percentage of Mg in the first electron transport layer is greater than a molar percentage of Mg in the second electron transport layer. ### Claim 9 (depends on 8) The light-emitting structure according to claim 8, wherein the molar percentage of Mg in the first electron transport layer is 10%-20%, and the molar percentage of Mg in the second electron transport layer is less than 5%. ### Claim 10 (depends on 5) The light-emitting structure according to claim 5, wherein at least one of the first light-emitting layer and the second light-emitting layer is a quantum dot light-emitting layer, and the first cathode and the second cathode are the same conductive layer. ### Claim 11 (depends on 5) The light-emitting structure according to claim 5, further comprising: a third light-emitting element comprising a third light-emitting layer, a third electron transport layer, and a third cathode, wherein the third cathode is in contact with the third electron transport layer, and an energy level of CBM of the third light-emitting layer is larger than that of the first light-emitting layer and smaller than that of the second light-emitting layer, an energy level of CBM of the third electron transport layer is smaller than that of the first electron transport layer and larger than that of the second electron transport layer. ### Claim 12 (depends on 11) The light-emitting structure according to claim 11, wherein a potential barrier of electrons from the third cathode to the third electron transport layer is larger than a potential barrier of electrons from the second cathode to the second electron transport layer and smaller than a potential barrier of electrons from the first cathode to the first electron transport layer. ### Claim 13 (depends on 11) The light-emitting structure according to claim 11, wherein the first electron transport layer comprises ZnMgO nanoparticles, the second electron transport layer comprises ZnO nanoparticles or ZnMgO nanoparticles, and the third electron transport layer comprises ZnMgO nanoparticles, and a molar percentage of Mg in the third electron transport layer is smaller than a molar percentage of Mg in the first electron transport layer and larger than a molar percentage of Mg in the second electron transport layer. ### Claim 14 (depends on 13) The light-emitting structure according to claim 13, wherein the molar percentage of Mg in the first electron transport layer is in a range of 10%-20%, the molar percentage of Mg in the second electron transport layer is less than 5%, and the molar percentage of Mg in the third electron transport layer is in a range of 5%40%. ### Claim 15 (depends on 11) The light-emitting structure according to claim 11, wherein an electron mobility of the third electron transport layer is larger than that of the first electron transport layer and smaller than that of the second electron transport layer. ### Claim 16 (depends on 5) The light-emitting structure according to claim 5, wherein an electron mobility of the first electron transport layer is smaller than that of the second electron transport layer. ### Claim 17 (depends on 5) The light-emitting structure according to claim 5, wherein the first light-emitting layer is configured to emit light of red and the second light-emitting layer is configured to emit light of blue. ### Claim 18 (depends on 1) A display panel, comprising a plurality of light-emitting structures arranged in an array, wherein each of the plurality of light-emitting structures is the light-emitting structure according to claim 1. ### Claim 19 (depends on 18) A display device, comprising the display panel according to claim 18.