# US 12,224,556 B2 · Light emitting device, projector, and display > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,224,556 B2 - Document ID: US12224556B2 - Status: Granted - Kind: B2 - Application number: 17/693,394 - Filed: 2022-03-13 - Published: 2022-09-15 - Granted: 2025-02-11 - Earliest claimed: 2021-03-15 - Assignees: Seiko Epson Corporation; Sophia School Corporation - Applicants: Seiko Epson Corporation; Sophia School Corporation - Inventors: Manabu Kudo; Katsumi Kishino - Web page: https://patentgrep.com/patent/US12224556B2 ## CPC - H01S 5/11: Comprising a photonic bandgap structure - H01S 5/34333: {with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser} - H10H 29/142: {Two-dimensional arrangements, e.g. asymmetric LED layout} - G03B 21/2033: {LED or laser light sources} - H01S 5/04253: {having specific optical properties, e.g. transparent electrodes} - H01S 5/04257: {having positive and negative electrodes on the same side of the substrate} - H01S 5/1042: {Optical microcavities, e.g. cavity dimensions comparable to the wavelength} - H01S 5/185: having only horizontal cavities, e.g. horizontal cavity surface-emitting lasers [HCSEL] (comprising a photonic bandgap structure H01S5/11) - H01S 5/2027: {Reflecting region or layer, parallel to the active layer, e.g. to modify propagation of the mode in the laser or to influence transverse modes} - H01S 5/34: comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers (H01S5/36 takes precedence) - H01S 2304/12: Pendeo epitaxial lateral overgrowth [ELOG], e.g. for growing GaN based blue laser diodes - H10H 20/819: characterised by their shape, e.g. curved or truncated substrates - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS - G03B: APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR (optical parts of such apparatus G02B; photosensitive materials or processes for photographic purposes G03C; apparatus for processing exposed photographic materials G03D) ## Abstract The light emitting device includes a substrate, and a laminated structure including columnar parts, wherein the columnar parts include a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting layer disposed between the first semiconductor layer and the second semiconductor layer, the light emitting layer has a c-plane and a facet plane, the second semiconductor layer is disposed on the c-plane and the facet plane, the first semiconductor layer has a first portion and a second portion smaller in diametrical size than the first portion, the second portion is disposed between the substrate and the first portion, and the c-plane and the second portion overlap each other, and the c-plane is smaller in diametrical size than the second portion in a plan view from a stacking direction of the first semiconductor layer and the light emitting layer. ## Claims ### Claim 1 A light emitting device comprising: a substrate; and a laminated structure including a plurality of columnar parts, wherein the columnar part includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type different from the first conductivity type, and a light emitting layer disposed between the first semiconductor layer and the second semiconductor layer, the first semiconductor layer is disposed between the substrate and the light emitting layer, the light emitting layer has a c-plane and a facet plane, the second semiconductor layer is disposed on the c-plane and the facet plane, the first semiconductor layer has a first portion and a second portion smaller in diametrical size than the first portion, the second portion is disposed between the substrate and the first portion, and the c-plane and the second portion overlap each other, and the c-plane is smaller in diametrical size than the second portion in a plan view from a stacking direction of the first semiconductor layer and the light emitting layer. ### Claim 2 (depends on 1) The light emitting device according to claim 1, wherein the light emitting layer is larger in diametrical size than the c-plane and the second portion. ### Claim 3 (depends on 1) The light emitting device according to claim 1, wherein a step is formed at a boundary between the first portion and the second portion. ### Claim 4 (depends on 1) The light emitting device according to claim 1, wherein the substrate is provided with an insulating layer having an opening part, and the second portion is disposed in the opening part. ### Claim 5 (depends on 4) The light emitting device according to claim 4, wherein the insulating layer is disposed between the substrate and the first portion. ### Claim 6 (depends on 1) The light emitting device according to claim 1, wherein in the plan view, a portion of the second semiconductor layer overlapping the c-plane is higher in impurity concentration than a portion of the second semiconductor layer overlapping the facet plane. ### Claim 7 (depends on 1) A projector comprising: the light emitting device according to claim 1. ### Claim 8 (depends on 1) A display comprising: the light emitting device according to claim 1.