# US 10,829,868 B2 · Manufacturing method of SiC composite substrate

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,829,868 B2
- Document ID: US10829868B2
- Status: Granted
- Kind: B2
- Application number: 15/759,285
- Filed: 2016-09-09
- Published: 2018-09-06
- Granted: 2020-11-10
- Earliest claimed: 2015-09-15
- Assignees: Shin-Etsu Chemical Co., Ltd.; Cusic Inc.
- Applicants: Shin-Etsu Chemical Co., Ltd.; CUSIC Inc.
- Inventors: Shoji Akiyama; Yoshihiro Kubota; Hiroyuki Nagasawa
- Web page: https://patentgrep.com/patent/US10829868B2

## CPC

- C30B 33/06: Joining of crystals
- C23C 16/01: on temporary substrates, e.g. substrates subsequently removed by etching
- C23C 16/325: {Silicon carbide}
- C23C 16/42: Silicides
- C30B 25/18: characterised by the substrate
- C30B 25/186: {being specially pre-treated by, e.g. chemical or physical means}
- C30B 29/36: Carbides
- H10P 90/1904: {Preparing vertically inhomogeneous wafers}
- 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
- 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)
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10

## Abstract

A manufacturing method of an SiC composite substrate 10 that includes a single crystal SiC layer 12 on a polycrystalline SiC substrate 11. After manufacturing a single crystal SiC layer supporting body 14 by providing the single crystal SiC layer 12 on one surface of a holding substrate 21 including Si. A polycrystalline SiC is deposited on the single crystal SiC layer 12 through chemical vapor deposition to manufacture an SiC laminated body 15 laminated with the single crystal SiC layer 12 and the polycrystalline SiC layer 11 having a thickness t on the holding substrate 21′. At the same time, the single crystal SiC layer supporting body 14 is heated at a temperature less than 1,414 degrees Celsius, and a portion of the thickness t of the polycrystalline SiC is deposited. Then, the holding substrate 21′ is physically and/or chemically removed.

## Claims

### Claim 1

A method for producing a SiC composite substrate comprising a monocrystalline SiC layer on a polycrystalline SiC substrate, the method comprising, in order, the steps of:
providing a monocrystalline SiC layer on one side of a support substrate made of silicon so as to produce a monocrystalline SiC layer carrier;
producing a SiC laminate comprising the monocrystalline SiC layer and a polycrystalline SiC substrate of thickness t stacked on the support substrate, by using a chemical vapor deposition process to deposit polycrystalline SiC on the monocrystalline SiC layer and then cooling, said deposition of the polycrystalline SiC comprising
(i) heating the monocrystalline SiC layer carrier to below 1,414° C. and depositing thereon only part of the polycrystalline SiC substrate, which is a thickness t1 of at least 30 μm, and
(ii) subsequently raising the temperature to 1,414° C. or above and additionally depositing polycrystalline SiC up to the thickness t, which is at least 100 μm and not more than 650 μm, while melting at least part of the support substrate; and
physically and/or chemically removing the support substrate.

### Claim 2 (depends on 1)

The SiC composite substrate production method of claim 1, wherein the chemical vapor deposition process is thermal chemical vapor deposition.

### Claim 3 (depends on 1)

The SiC composite substrate production method of claim 1, wherein an intermediate layer made of silicon oxide, silicon nitride or silicon oxynitride is provided between the support substrate and the monocrystalline SiC layer.

### Claim 4 (depends on 1)

The SiC composite substrate production method of claim 1, wherein the monocrystalline SiC layer is provided by transferring onto the support substrate a monocrystalline SiC thin film exfoliated from a monocrystalline SiC substrate by ion-implantation exfoliation.

### Claim 5 (depends on 1)

The SiC composite substrate production method claim 1, wherein the monocrystalline SiC layer is provided by heteroepitaxial growth of SiC on the support substrate.

### Claim 6 (depends on 1)

The SiC composite substrate production method of claim 1, wherein the thickness t1 of the polycrystalline SiC deposited when the monocrystalline SiC carrier is heated to below 1,414° C. is at least 0.075t and not more than 0.5t, and a thickness t2 of the polycrystalline SiC deposited when the monocrystalline SiC carrier is heated to 1,414° C. or more is at least 0.5t and not more than 0.925t.

### Claim 7 (depends on 1)

The SiC composite substrate production method of claim 1, wherein the amount of bow in the SiC composite is 100 μm or less.

### Claim 8 (depends on 1)

The SiC composite substrate production method of claim 1 wherein the amount of bow in the SiC composite is between −50 μm and +75 μm.