SIC SINGLE CRYSTAL AND METHOD FOR PRODUCING SAME

• US 20160237590A1
• Filed: 08/27/2014
• Published: 08/18/2016
• Est. Priority Date: 09/27/2013
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Nippon Steel & Sumitomo Metal Corporation (Nippon Steel Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: DAIKOKU, Hironori, KADO, Motohisa, KAMEI, Kazuhito, KUSUNOKI, Kazuhiko
• Granted Patent: US 10,450,671 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C30B 19/02 using molten solvents, e.g. flux
• CPC Class Codes: C30B 19/062 Vertical dipping system
• CPC Class Codes: C30B 19/068 Substrate holders
• CPC Class Codes: C30B 19/08 Heating of the reaction chamber or the substrate
• CPC Class Codes: C30B 19/10 Controlling or regulating controlling or regulating in general G05
• CPC Class Codes: C30B 19/12 characterised by the substrate
• CPC Class Codes: C30B 29/36 Carbides
• CPC Class Codes: C30B 9/10 Metal solvents
• CPC Class Codes: H01L 21/02529 Silicon carbide
• CPC Class Codes: H01L 21/02598 monocrystalline
• CPC Class Codes: H01L 21/02609 Crystal orientation
• CPC Class Codes: H01L 21/02628 using solutions
• CPC Class Codes: H01L 29/045 by their particular orientation of crystalline planes
• CPC Class Codes: H01L 29/1608 Silicon carbide

Abstract

Provided is a SiC single crystal that has a large growth thickness and contains no inclusions. A SiC single crystal grown by a solution process, wherein the total length M of the outer peripheral section formed by the {1-100} faces on the {0001} growth surface of the SiC single crystal, and the length P of the outer periphery of the growth surface of the SiC single crystal, satisfy the relationship M/P≦0.70, and the length in the growth direction of the SiC single crystal is 2 mm or greater.

Claims

1. A SiC single crystal grown by a solution process, wherein:

the total length M of the outer peripheral section formed by the {1-100} faces on the {0001} growth surface of the SiC single crystal, and the length P of the outer periphery of the growth surface of the SiC single crystal, satisfy the relationship M/P≦

0.70, and the length in the growth direction of the SiC single crystal is 2 mm or greater.

2. The SiC single crystal according to claim 1, wherein the SiC single crystal has a concave crystal growth surface.

3. The SiC single crystal according to claim 2, wherein the maximum angle θ

of the inclination of the concave crystal growth surface with respect to the onset axis plane of growth of the SiC single crystal is in the range of 0<

θ

≦

8°

.

4. A method for producing a SiC single crystal in which a SiC seed crystal substrate held on a seed crystal holding shaft is contacted with a Si—

C solution having a temperature gradient such that the temperature decreases from the interior toward the surface, in a crucible, to grow a SiC single crystal, wherein the method comprises;

growing the SiC single crystal from the {0001} face of the seed crystal substrate so that the grown SiC single crystal has a length in the growth direction of 2 mm or greater, and

reducing the heat loss from the <

11-20>

direction to be lower than the heat loss from the <

1-100>

direction, and

wherein the ratio S/C of the diameter S of the seed crystal substrate to the inner diameter C of the crucible satisfies the relationship 0.50≦

S/C<

1.0.

5. The method for producing a SiC single crystal according to claim 4, wherein the method comprises forming a meniscus between the seed crystal substrate and the Si—

C solution.

6. The method for producing a SiC single crystal according to claim 4, wherein the method comprises controlling the temperature of the Si—

C solution so that the temperature of the Si—

C solution at the outer peripheral sections directly below the interface with the crystal growth surface is lower than the temperature of the Si—

C solution at the center section directly below the interface with the crystal growth surface, and causing flow of the Si—

C solution from the center section to the outer peripheral sections directly below the interface with the crystal growth surface.

7. The method for producing a SiC single crystal according to claim 5, wherein the method comprises controlling the temperature of the Si—

C solution so that the temperature of the Si—

C solution at the outer peripheral sections directly below the interface with the crystal growth surface is lower than the temperature of the Si—

C solution at the center section directly below the interface with the crystal growth surface, and causing flow of the Si—

C solution from the center section to the outer peripheral sections directly below the interface with the crystal growth surface.