Method for producing SiC single crystal

Patent metadata

Field	Value
Publication number	US-10119199-B2
Application number	US-201615558683-A
Country	US
Kind code	B2
Filing date	Mar 17, 2016
Priority date	Mar 18, 2015
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A production method according an embodiment of the present invention is to produce a SiC single crystal by a solution growth technique, and includes a formation step and a growth step. In the formation step, material of Si—C solution contained in a crucible is melted, and a Si—C solution is formed. In the growth step, a SiC seed crystal attached to a bottom end of a seed shaft is brought into contact with the Si—C solution, and a SiC single crystal is grown on a crystal growth surface of the SiC seed crystal. In the growth step, while a temperature of the Si—C solution is being raised, the SiC single crystal is grown. The SiC single crystal production method according to the embodiment facilitates production of a SiC single crystal of a desired polytype.

First claim

The invention claimed is:

1. A method for producing a SIC single crystal by a solution growth technique, the method comprising:
a formation step of forming a Si—C solution by melting material for the Si—C solution contained in a crucible; and
a growth step of bringing a SiC seed crystal attached to a bottom end of a seed shaft into contact with the Si—C solution and growing a SiC single crystal on a crystal growth surface of the SiC seed crystal, wherein
in the growth step, while a temperature of the Si—C solution is being raised, the SiC single crystal is grown.

2. The method for producing a SiC single crystal according to claim 1 , wherein
in the growth step, a crystal growth temperature at the end of growth of the SiC single crystal is higher than a crystal growth temperature at the start of growth of the SiC single crystal.

3. The method for producing a SiC single crystal according to claim 1 , wherein
in the growth step, a meniscus is formed between a liquid surface of the Si—C solution and the crystal growth surface of the SIC seed crystal.

4. The method for producing a SiC single crystal according to claim 3 , wherein
the meniscus has a height of 3 mm or less.

5. A method for producing a SIC single crystal, the method comprising:
a formation step of forming a Si—C solution by melting material for the Si—C solution contained in a crucible,
a first growth step of bringing a first SiC seed crystal attached to a bottom end of a seed shaft into contact with the Si—C solution and growing a first SIC single crystal on a crystal growth surface of the first SiC seed crystal, wherein
in the first growth step, while a temperature of the Si—C solution is being raised, the first SiC single crystal is grown,
a preparation step of preparing the first SIC single crystal; and
a second growth step of using the first SiC single crystal as a second seed crystal and growing a second SiC single crystal on a crystal growth surface of the second SiC seed crystal by a sublimation-recrystallization technique or a high-temperature CVD technique.

6. The method for producing a SiC single crystal according to claim 2 , wherein
in the growth step, a meniscus is formed between a liquid surface of the Si—C solution and the crystal growth surface of the SiC seed crystal.

7. The method for producing a SiC single crystal according to claim 6 , wherein
the meniscus has a height of 3 mm or less.

8. The method for producing a SiC single crystal according to claim 5 , wherein
in the first growth step, a crystal growth temperature at the end of growth of the first SiC single crystal is higher than a crystal growth temperature at the start of growth of the first SiC single crystal.

9. The method for producing a SiC single crystal according to claim 5 , wherein
in the first growth step, a meniscus is formed between a liquid surface of the Si—C solution and the crystal growth surface of the first SIC seed crystal.

10. The method for producing a SiC single crystal according to claim 8 , wherein
in the first growth step, a meniscus is formed between a liquid surface of the Si—C solution and the crystal growth surface of the first SIC seed crystal.

11. The method for producing a SiC single crystal according to claim 9 , wherein
the meniscus has a height of 3 mm or less.

12. The method for producing a SiC single crystal according to claim 10 , wherein
the meniscus has a height of 3 mm or less.

Assignees

• Toyota Motor Co Ltd

Inventors

• Seki Kazuaki
• Kamei Kazuhito
• Kusunoki Kazuhiko
• Danno Katsunori
• Daikoku Hironori
• Doi Masayoshi

Classifications

• C30B19/10 Primary

  Controlling or regulating (controlling or regulating in general G05) · CPC title

• C30B23/025

  characterised by the substrate · CPC title

• C30B29/68

  Crystals with laminate structure, e.g. "superlattices" · CPC title

• C30B25/20

  the substrate being of the same materials as the epitaxial layer · CPC title

• C30B29/36

  Carbides · CPC title