# US 10,374,125 B2 · Light-emitting device having a patterned substrate and the method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,374,125 B2 - Document ID: US10374125B2 - Status: Granted - Kind: B2 - Application number: 16/049,337 - Filed: 2018-07-30 - Published: 2019-02-28 - Granted: 2019-08-06 - Earliest claimed: 2006-07-28 - Assignees: Epistar Corporation - Applicants: Epistar Corporation - Inventors: Ta-Cheng Hsu; Ching-Shian Yeh; Chao-Shun Huang; Ying-Yong Su; Ya-Lan Yang; Ya-Ju Lee - Web page: https://patentgrep.com/patent/US10374125B2 ## CPC - H10H 20/82: Roughened surfaces, e.g. at the interface between epitaxial layers - H10H 20/01335: {the light-emitting regions comprising nitride materials} - H10H 20/825: containing nitrogen, e.g. GaN - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract A light-emitting device comprises a textured substrate comprising a plurality of textured structures, wherein the textured structures and the textured substrate are both composed of sapphire; and a light-emitting stack overlaying the textured substrate, comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein each of the plurality of textured structures comprises a top portion having a first top-view shape, and a bottom portion parallel to the top portion and having a second top-view shape, wherein the first top-view shape comprises a circle or an ellipse, the first top-view shape comprises a first periphery and the second top-view shape comprises a second periphery, the first periphery is enclosed by the second periphery, and various distances are between each of the first periphery and the second periphery. ## Claims ### Claim 1 A light-emitting device, comprising: a sapphire substrate comprising a flat surface, a lower surface, and a plurality of depressions between the flat surface and the lower surface; a semiconductor buffer layer filled the plurality of depressions and formed on the flat surface; and a light-emitting stack comprising III-V semiconductor, overlaying the semiconductor buffer layer, comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein in a plan view of the light-emitting device, one of the plurality of depressions comprises an opening top portion having a first top-view shape and a bottom portion having a second top-view shape, wherein in a cross-sectional view of the light-emitting device, the one of the plurality of depressions comprises a sidewall portion connecting the opening top portion and the bottom portion, and wherein in a cross-sectional view of the light-emitting device, the sidewall portion near the opening top portion or the bottom portion is a curve. ### Claim 2 (depends on 1) The light-emitting device according to claim 1, wherein the opening top portion is closer to the light-emitting stack than the bottom portion to the light-emitting stack. ### Claim 3 (depends on 1) The light-emitting device according to claim 1, wherein the first top-view shape is different from the second top-view shape. ### Claim 4 (depends on 1) The light-emitting device according to claim 1, wherein the first top-view shape comprises a circle or an ellipse. ### Claim 5 (depends on 1) The light-emitting device according to claim 1, wherein the second top-view shape comprises a triangle. ### Claim 6 (depends on 1) The light-emitting device according to claim 1, wherein the semiconductor buffer layer comprises Ill-nitride materials. ### Claim 7 (depends on 6) The light-emitting device according to claim 6, wherein the semiconductor buffer layer comprises AN. ### Claim 8 (depends on 1) The light-emitting device according to claim 1, wherein the sidewall portion comprises three symmetric planes. ### Claim 9 (depends on 1) The light-emitting device according to claim 1, wherein the bottom portion comprises an area smaller than an area of the opening top portion. ### Claim 10 (depends on 1) The light-emitting device according to claim 1, wherein the bottom portion is flat. ### Claim 11 A light-emitting device, comprising: a sapphire substrate comprising a flat surface, a lower surface, and a plurality of depressions between the flat surface and the lower surface; a semiconductor buffer layer filled the plurality of depressions and formed on the flat surface; and a light-emitting stack comprising III-V semiconductor, overlaying the semiconductor buffer layer, comprising a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, wherein in a plan view of the light-emitting device, one of the plurality of depressions comprises an opening top portion having a top-view shape, wherein in a cross-sectional view of the light-emitting device, the one of the plurality of depressions comprises a plurality of sidewall planes intersected at a bottom point, and wherein in a cross-sectional view of the light-emitting device, the sidewall portion near the opening top portion or the bottom portion is a curve. ### Claim 12 (depends on 11) The light-emitting device according to claim 11, wherein the opening top portion is closer to the light-emitting stack than the bottom point to the light-emitting stack. ### Claim 13 (depends on 11) The light-emitting device according to claim 11, wherein the top-view shape comprises a circle or an ellipse. ### Claim 14 (depends on 11) The light-emitting device according to claim 11, wherein the semiconductor buffer layer comprises Ill-nitride materials. ### Claim 15 (depends on 14) The light-emitting device according to claim 14, wherein the semiconductor buffer layer comprises AlN. ### Claim 16 (depends on 11) The light-emitting device according to claim 11, wherein the plurality of sidewall planes comprises sapphire R plane. ### Claim 17 (depends on 11) The light-emitting device according to claim 11, wherein the flat surface comprises sapphire C plane.