# US 2025/0146940 A1 · Inspection method of light-emitting element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0146940 A1 - Document ID: US20250146940A1 - Status: Published application - Kind: A1 - Application number: 19/014,377 - Filed: 2025-01-09 - Published: 2025-05-08 - Earliest claimed: 2022-09-06 - Assignees: Japan Display Inc. - Applicants: Japan Display Inc. - Inventors: Masanobu IKEDA - Web page: https://patentgrep.com/patent/US20250146940A1 ## CPC - G01N 21/6489: {Photoluminescence of semiconductors} - G01N 21/66: electrically excited, e.g. electroluminescence - H10H 20/80: Constructional details - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract Disclosed is a method for inspecting a light-emitting element, the method including: forming a buffer layer over an amorphous substrate; forming, over the buffer layer, an n-type cladding layer, an emission layer, and a p-type cladding layer each including an inorganic semiconductor to form a plurality of semiconductor layers arranged in a matrix form having a plurality of rows and a plurality of columns; forming an anode and a cathode over each of the plurality of semiconductor layers to form a plurality of light-emitting elements; and acquiring at least one of a photoluminescence property or an electroluminescence property of the plurality of light-emitting elements using a first detector and a second detector. The buffer layer has a function to promote crystallization of the semiconductor layers. The photoluminescence property is acquired before forming the anode and the cathode. The electroluminescence property is acquired after forming the anode and the cathode. ## Claims ### Claim 1 A method for inspecting a light-emitting element, the method comprising: forming a buffer layer over an amorphous substrate; forming, over the buffer layer, an n-type cladding layer, an emission layer, and a p-type cladding layer each including an inorganic semiconductor to form a plurality of semiconductor layers arranged in a matrix form having a plurality of rows and a plurality of columns; forming an anode and a cathode over each of the plurality of semiconductor layers to form a plurality of light-emitting elements; and acquiring at least one of a photoluminescence property or an electroluminescence property of the plurality of light-emitting elements using a first detector and a second detector, wherein the buffer layer has a function to promote crystallization of the semiconductor layers, the photoluminescence property is acquired before forming the anode and the cathode, and the electroluminescence property is acquired after forming the anode and the cathode. ### Claim 2 (depends on 1) The method according to claim 1, wherein the acquisition of the photoluminescence property comprises: irradiating a first element group including two or more light-emitting elements selected from the plurality of light-emitting elements with light and measuring photoluminescence of the light-emitting elements included in the first element group with the first detector; and irradiating a second element group including two or more light-emitting elements selected from the plurality of light-emitting elements with light and measuring photoluminescence of the light-emitting elements included in the second element group with the second detector, and the acquisition of the electroluminescence property comprises: supplying electric power to a third element group including two or more light-emitting elements selected from the plurality of light-emitting elements and measuring electroluminescence of the light-emitting elements included in the third element group with the first detector, and supplying electric power to a fourth element group including two or more light-emitting elements selected from the plurality of light-emitting elements and measuring electroluminescence of the light-emitting elements included in the fourth element group with the second detector. ### Claim 3 (depends on 1) The method according to claim 1, wherein both the photoluminescence property and the electroluminescence property are acquired. ### Claim 4 (depends on 2) The method according to claim 2, wherein at least one light-emitting element among the plurality of light-emitting elements is included in both the first element group and the second element group, and the method further comprises calibrating the first detector and the second detector using the photoluminescence of the at least one light-emitting element. ### Claim 5 (depends on 2) The method according to claim 2, wherein at least one light-emitting element among the plurality of light-emitting elements is included in both the third element group and the fourth element group, and the method further comprises calibrating the first detector and the second detector using the electroluminescence of the at least one light-emitting element. ### Claim 6 (depends on 2) The method according to claim 2, wherein the light-emitting elements included in the first element group are the light-emitting elements included in the third element group, and the light-emitting elements included in the second element group are the light-emitting elements included in the fourth element group. ### Claim 7 (depends on 1) The method according to claim 1, further comprising: forming, over the amorphous substrate, a plurality of alignment marks for alignment of the first detector and the second detector, wherein the plurality of alignment marks includes the inorganic semiconductor. ### Claim 8 (depends on 7) The method according to claim 7, wherein the plurality of alignment marks is formed outside a region in which the plurality of light-emitting elements is arranged. ### Claim 9 (depends on 7) The method according to claim 7, wherein at least one of the plurality of alignment marks is formed between adjacent light-emitting elements. ### Claim 10 (depends on 1) The method according to claim 1, wherein the first detector and the second detector are configured so that a distance from the amorphous substrate and/or an angle with respect to the amorphous substrate can be adjusted. ### Claim 11 (depends on 1) The method according to claim 1, wherein the acquisition of the electroluminescence property comprises supplying electric power to the plurality of light-emitting elements through an inspection substrate, the inspection substrate comprises: a light-transmitting substrate transmitting visible light; a first wiring over the light-transmitting substrate; and a second wiring over the light-transmitting substrate, the first wiring is configured so as to be electrically connected to the n-type cladding layer when the inspection substrate is arranged over the plurality of light-emitting elements, and the second wiring is configured so as to be electrically connected to the anodes of at least two light-emitting elements when the inspection substrate is arranged over the plurality of light-emitting elements. ### Claim 12 (depends on 1) The method according to claim 1, wherein the n-type cladding layer continues between adjacent light-emitting elements. ### Claim 13 (depends on 11) The method according to claim 11, wherein the at least two light-emitting elements are arranged in a direction of the row or the column. ### Claim 14 (depends on 11) The method according to claim 11, wherein the at least two light-emitting elements are arranged so as to sandwich another light-emitting element, the inspection substrate further comprises a light-shielding film, and the light-shielding film is configured to overlap the other light-emitting element when the inspection substrate is arranged over the plurality of light-emitting elements.