Method of manufacturing silicon carbide substrate

Patent metadata

Field	Value
Publication number	US-9346187-B2
Application number	US-201213484724-A
Country	US
Kind code	B2
Filing date	May 31, 2012
Priority date	Jun 2, 2011
Publication date	May 24, 2016
Grant date	May 24, 2016

Abstract

A method of manufacturing a silicon carbide substrate includes the steps of preparing an ingot of single crystal silicon carbide and obtaining a substrate by cutting the ingot. Then, in the step of obtaining a substrate, cutting proceeds in a direction α in which an angle β formed with respect to a <11-20> direction or a <1-100> direction of the ingot is 15°±5° in an orthogonal projection on a {0001} plane.

First claim

What is claimed is:

1. A method of manufacturing a silicon carbide substrate, comprising the steps of:
preparing a crystal of single crystal silicon carbide having a cleavage direction that appears every 30 degrees in an orthogonal projection on a {0001} plane; and
obtaining a substrate by cutting said crystal, wherein
in said step of obtaining a substrate, the cutting of said crystal proceeds in a direction in which an angle formed with respect to a <11-20> direction or a <1-100> direction of said crystal is 15°±5° in the orthogonal projection on the {0001} plane, and
in said step of obtaining a substrate, said crystal is cut such that a ratio of a diameter to a thickness of said substrate is not smaller than 100.

2. The method of manufacturing a silicon carbide substrate according to claim 1 , wherein
in said step of obtaining a substrate, cutting proceeds in a direction in which an angle formed with respect to the <11-20> direction or the <1-100> direction of said crystal is 15°±2° in an orthogonal projection on a {0001} plane.

3. The method of manufacturing a silicon carbide substrate according to claim 1 , wherein
said crystal grows in a <0001> direction.

4. The method of manufacturing a silicon carbide substrate according to claim 1 , wherein
said crystal has a diameter not smaller than 2 inches.

5. The method of manufacturing a silicon carbide substrate according to claim 1 , wherein
in said step of obtaining a substrate, said crystal is cut by wire cutting.

6. The method of manufacturing a silicon carbide substrate according to claim 5 , wherein a feed speed of said wire is not less than 300 m/min and not more than 700 m/min.

7. The method of manufacturing a silicon carbide substrate according to claim 5 , wherein a tensile force of said wire is not less than 35 N and not more than 50 N.

8. The method of manufacturing a silicon carbide substrate according to claim 1 , wherein a cutting speed of said crystal is not less than 1 mm/h and not more than 3 mm/h.

Assignees

• Okita Kyoko
• Sumitomo Electric Industries

Inventors

• Okita Kyoko

Classifications

• B28D5/045 Primary

  by cutting with wires or closed-loop blades (B28D5/042 takes precedence) · CPC title

• B28D5/04 Primary

  by tools other than rotary type, e.g. reciprocating tools {(B28D5/0005 takes precedence)} · CPC title

• C30B33/06

  Joining of crystals · CPC title

• C30B33/00

  After-treatment of single crystals or homogeneous polycrystalline material with defined structure (C30B31/00 takes precedence) · CPC title

• Y10T83/04

  Processes · CPC title