SiC single crystal and method for producing same

Patent metadata

Field	Value
Publication number	US-9732437-B2
Application number	US-201514824811-A
Country	US
Kind code	B2
Filing date	Aug 12, 2015
Priority date	Sep 9, 2014
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

A low-resistance p-type SiC single crystal containing no inclusions is provided. This is achieved by a method for producing a SiC single crystal wherein a SiC seed crystal substrate 14 is contacted with a Si—C solution 24 having a temperature gradient in which the temperature falls from the interior toward the surface, to grow a SiC single crystal, and wherein the method comprises: using, as the Si—C solution, a Si—C solution containing Si, Cr and Al, wherein the Al content is 3 at % or greater based on the total of Si, Cr and Al, and making the temperature gradient y (° C./cm) in the surface region of the Si—C solution 24 satisfy the following formula (1): y≧0.15789x+21.52632 (1) wherein x represents the Al content (at %) of the Si—C solution.

First claim

What is claimed is:

1. A method for producing a SiC single crystal wherein a SiC seed crystal substrate is contacted with a Si—C solution having a temperature gradient in which temperature falls from an interior toward a surface, to grow the SiC single crystal, the method comprising:
using, as the Si—C solution, a solution containing Si, Cr and Al, wherein an Al content is 3 at % or greater based on a total of Si, Cr and Al; and
making a temperature gradient y (° C./cm) in a surface region of the Si—C solution satisfy the following formula (1):
y≧ 0.15789 x+ 21.52632  (1)

wherein x represents the Al content (at %) of the Si—C solution.

2. The method for producing a SiC single crystal according to claim 1 , comprising limiting the temperature gradient in the surface region of the Si—C solution to a range of 28 to 55° C./cm with the Al content in a range of 3 to 41 (at %) in the Si—C solution.

Assignees

• Toyota Motor Co Ltd

Inventors

• Shirai Takayuki

Classifications

• C30B19/106

  adding crystallising material or reactants forming it in situ to the liquid · CPC title

• C30B19/067

  Boots or containers · CPC title

• C30B9/06

  using as solvent a component of the crystal composition · CPC title

• C30B19/10 Primary

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

• C30B19/08

  Heating of the reaction chamber or the substrate · CPC title