# US 11,443,946 B2 · Method for manufacturing silicon carbide base body, method for manufacturing semiconductor device, silicon carbide base body, and semiconductor device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,443,946 B2 - Document ID: US11443946B2 - Status: Granted - Kind: B2 - Application number: 17/004,264 - Filed: 2020-08-27 - Published: 2021-07-15 - Granted: 2022-09-13 - Earliest claimed: 2020-01-09 - Assignees: Kabushiki Kaisha Toshiba - Applicants: Kabushiki Kaisha Toshiba - Inventors: Johji Nishio; Chiharu Ota - Web page: https://patentgrep.com/patent/US11443946B2 ## CPC - H10P 14/3822: {Controlling the interface between substrate and epitaxial layer, e.g. by ion implantation followed by annealing} - C23C 14/0635: {Carbides} - C23C 14/5873: {Removal of material} - C23C 16/325: {Silicon carbide} - C23C 16/56: After-treatment - C30B 23/025: {characterised by the substrate} - C30B 25/20: the substrate being of the same materials as the epitaxial layer - C30B 29/36: Carbides - H10D 8/411: {PN diodes having planar bodies} - H10D 62/405: {Orientations of crystalline planes} - H10D 62/8325: {Silicon carbide} - H10P 14/22: using physical deposition, e.g. vacuum deposition or sputtering - H10P 14/24: using chemical vapour deposition [CVD] - H10P 14/2904: {Silicon carbide} - H10P 14/2925: {Surface structures} - H10P 14/2926: {Crystal orientations} - H10P 14/3208: {Silicon carbide} - H10P 14/3258: {Crystal orientation} - H10P 14/3408: {Silicon carbide} - H10P 14/3466: {Crystal orientation} - H10P 14/36: {characterised by treatments done before the formation of the materials} - H10D 8/00: Diodes (variable-capacitance diodes H10D1/64; gated diodes H10D12/00) - H10D 12/441: {Vertical IGBTs} - H10D 30/66: Vertical DMOS [VDMOS] FETs - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - C30B: SINGLE-CRYSTAL GROWTH (by using ultra-high pressure, e.g. for the formation of diamonds, B01J3/06); UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL (zone-refining of metals or alloys C22B); PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (casting of metals, casting of other substances by the same processes or devices B22D; working of plastics B29; modifying the physical structure of metals or alloys C21D, C22F); SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (for producing semiconductor devices or parts thereof H10); APPARATUS THEREFOR - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract According to one embodiment, a method for manufacturing a silicon carbide base body is disclosed. The method can include preparing a first base body including silicon carbide. The first base body includes a first base body surface tilted with respect to a (0001) plane of the first base body. A first line segment where the first base body surface and the (0001) plane of the first base body intersect is along a [11-20] direction of the first base body. The method can include forming a first layer at the first base body surface. The first layer includes silicon carbide. The method can include removing a portion of the first layer. The first-layer surface is tilted with respect to a (0001) plane of the first layer. A second line segment where the first-layer surface and the (0001) plane of the first layer intersect is along a [−1100] direction. ## Claims ### Claim 1 A method for manufacturing a silicon carbide base body, the method comprising: preparing a first base body including silicon carbide, the first base body including a first base body surface tilted with respect to a (0001) plane of the first base body so that a first line segment where the first base body surface and the (0001) plane of the first base body intersect is along a [11-20] direction of the first base body; forming a first layer at the first base body surface, the first layer including silicon carbide; and removing a portion of the first layer, a first-layer surface of the first layer being exposed by the removing of the portion, the first-layer surface being tilted with respect to a (0001) plane of the first layer so that a second line segment where the first-layer surface and the (0001) plane of the first layer intersect is along a [−1100] direction. ### Claim 2 (depends on 1) The method according to claim 1, wherein the first base body surface is tilted in a <−1100> direction with respect to the (0001) plane of the first base body. ### Claim 3 (depends on 1) The method according to claim 1, wherein a third angle between the first line segment and the [11-20] direction of the first base body is ±5 degrees or less. ### Claim 4 (depends on 1) The method according to claim 1, wherein a first angle between the first base body surface and the (0001) plane of the first base body is not less than 2 degrees and not more than 8 degrees. ### Claim 5 (depends on 1) The method according to claim 1, wherein the first-layer surface is tilted in a <11-20> direction with respect to the (0001) plane of the first base body. ### Claim 6 (depends on 1) The method according to claim 1, wherein a fourth angle between the second line segment and the [−1100] direction of the first layer is ±5 degrees or less. ### Claim 7 (depends on 1) The method according to claim 1, wherein a second angle θ2 between the first-layer surface and the (0001) plane of the first layer is not less than 2 degrees and not more than 8 degrees. ### Claim 8 (depends on 7) The method according to claim 7, wherein a thickness of the first layer along a direction perpendicular to the (0001) plane of the first base body before the removing of the portion of the first layer is greater than (tanθ2)×L1, and L1 is a length of the first base body along the [11-20] direction of the first base body. ### Claim 9 (depends on 1) The method according to claim 1, wherein heat treatment of the first base body is performed before the forming of the first layer. ### Claim 10 (depends on 9) The method according to claim 9, wherein a temperature of the heat treatment is not less than 1100° C. and not more than 1600° C., and a time of the heat treatment is 10 minutes or more. ### Claim 11 (depends on 9) The method according to claim 9, wherein an atmosphere of the heat treatment includes at least one selected from the group consisting of argon, helium, neon, and nitrogen. ### Claim 12 (depends on 1) The method according to claim 1, wherein the forming of the first layer includes forming the first layer by at least one of sublimation or chemical vapor deposition. ### Claim 13 (depends on 1) The method according to claim 1, wherein the forming of the first layer includes forming at least a portion of the first layer by step-flow growth. ### Claim 14 A method for manufacturing a semiconductor device, the method comprising: preparing a silicon carbide base body, the silicon carbide base body including a first base body including silicon carbide, the first base body including a first base body surface tilted with respect to a (0001) plane of the first base body so that a first line segment where the first base body surface and the (0001) plane of the first base body intersect is along a [11-20] direction of the first base body, and a first layer provided at the first base body surface, the first layer including silicon carbide and including a first-layer surface and a first-layer opposite-surface, the first-layer opposite-surface being between the first base body surface and the first-layer surface, the first-layer surface being tilted with respect to a (0001) plane of the first layer so that a second line segment where the first-layer surface and the (0001) plane of the first layer intersect is along a [−1100] direction; and forming a second layer at the first-layer surface, the second layer including silicon carbide. ### Claim 15 (depends on 14) The method according to claim 14, wherein the second layer includes a threading edge dislocation connected to a basal plane dislocation included in the first layer. ### Claim 16 A silicon carbide base body, comprising: a first base body including silicon carbide, the first base body including a first base body surface tilted with respect to a (0001) plane of the first base body so that a first line segment where the first base body surface and the (0001) plane of the first base body intersect is along a [11-20] direction of the first base body; and a first layer provided at the first base body surface, the first layer including silicon carbide and including a first-layer surface and a first-layer opposite-surface, the first-layer opposite-surface being between the first base body surface and the first-layer surface, the first-layer surface being tilted with respect to a (0001) plane of the first layer so that a second line segment where the first-layer surface and the (0001) plane of the first layer intersect is along a [−1100] direction. ### Claim 17 (depends on 16) The silicon carbide base body according to claim 16, further comprising: a second base body, the first base body being between the second base body and the first layer, the second base body including a second base body surface and a second base body opposite-surface, the second base body surface being between the second base body opposite-surface and the first base body, an angle between the second base body opposite-surface and the (0001) plane of the first base body being less than an angle between the first base body surface and the (0001) plane of the first base body and less than an angle between the first-layer surface and the (0001) plane of the first base body. ### Claim 18 A semiconductor device, comprising: a first base body including silicon carbide, the first base body including a first base body surface tilted with respect to a (0001) plane of the first base body so that a first line segment where the first base body surface and the (0001) plane of the first base body intersect is along a [11-20] direction of the first base body; a first layer provided at the first base body surface, the first layer including silicon carbide and including a first-layer surface and a first-layer opposite-surface, the first-layer opposite-surface being between the first base body surface and the first-layer surface, the first-layer surface being tilted with respect to a (0001) plane of the first layer so that a second line segment where the first-layer surface and the (0001) plane of the first layer intersect is along a [−1100] direction; and a second layer provided at the first-layer surface, the second layer including silicon carbide. ### Claim 19 (depends on 18) The device according to claim 18, further comprising: a second base body, the first base body being between the second base body and the first layer, the second base body including a second base body surface and a second base body opposite-surface, the second base body surface being between the second base body opposite-surface and the first base body, an angle between the second base body opposite-surface and the (0001) plane of the first base body being less than an angle between the first base body surface and the (0001) plane of the first base body and less than an angle between the first-layer surface and the (0001) plane of the first base body.