Method of manufacturing silicon carbide ingot, silicon carbide seed substrate, silicon carbide substrate, semiconductor device and method of manufacturing semiconductor device

Patent metadata

Field	Value
Publication number	US-2017191183-A1
Application number	US-201515313571-A
Country	US
Kind code	A1
Filing date	May 21, 2015
Priority date	May 29, 2014
Publication date	Jul 6, 2017
Grant date	—

Abstract

A method of manufacturing a silicon carbide ingot includes the steps of: preparing a silicon carbide seed substrate having a first main surface and a second main surface located opposite the first main surface; forming a metal carbide film on the second main surface at a temperature of not more than 2000° C.; and growing a silicon carbide single crystal on the first main surface by sublimation, while supporting the silicon carbide seed substrate having the metal carbide film formed thereon by a supporting member. In the growing step, a supported portion of the surface of the silicon carbide seed substrate supported by the supporting member is in a region other than a region where the metal carbide film has been formed.

First claim

1 : A method of manufacturing a silicon carbide ingot, comprising the steps of:
preparing a silicon carbide seed substrate having a first main surface and a second main surface located opposite the first main surface; forming a metal carbide film on the second main surface at a temperature of not more than 2000° C.; and growing a silicon carbide single crystal on the first main surface by sublimation, while supporting the silicon carbide seed substrate having the metal carbide film formed thereon by a supporting member, in the growing step, a supported portion of the surface of the silicon carbide seed substrate supported by the supporting member being in a region other than a region where the metal carbide film has been formed.

2 : The method of manufacturing a silicon carbide ingot according to claim 1 , wherein
the metal carbide film includes at least one of titanium carbide, vanadium carbide and zirconium carbide.

3 : The method of manufacturing a silicon carbide ingot according to claim 1 , wherein
the step of forming a metal carbide film includes the steps of
forming a metal film on the second main surface, and
carbonizing the metal film.

4 : The method of manufacturing a silicon carbide ingot according to claim 3 , wherein
the step of carbonizing the metal film includes the steps of
placing the silicon carbide seed substrate on a carbon base, with the first main surface facing downward, and
heating the metal film while supplying carbon to the metal film.

5 : The method of manufacturing a silicon carbide ingot according to claim 3 , wherein
the step of forming a metal carbide film further includes the step of, after the step of carbonizing the metal film, planarizing the metal carbide film.

6 : The method of manufacturing a silicon carbide ingot according to claim 1 , wherein
in the growing step,
the silicon carbide seed substrate is disposed above and at a distance from the source material,
the first main surface faces the source material, and
the supported portion is at the end of the first main surface.

7 : A silicon carbide seed substrate, comprising a first main surface and a second main surface located opposite the first main surface,
the first main surface being a crystal growth surface, the second main surface having a metal carbide film thereon, the metal carbide film including at least one of titanium carbide, vanadium carbide and zirconium carbide.

8 : The silicon carbide seed substrate according to claim 7 , wherein
a film thickness of the metal carbide film is not less than 0.1 μm and not more than 1.0 mm.

9 : The silicon carbide seed substrate according to claim 7 , wherein
a coefficient of variation of the film thickness of the metal carbide film is not more than 20%.

10 : A method of manufacturing a silicon carbide ingot, comprising the steps of:
preparing the silicon carbide seed substrate according to claim 7 ; and growing a silicon carbide single crystal on the first main surface by sublimation, while supporting the silicon carbide seed substrate by a supporting member, in the growing step, a supported portion of the surface of the silicon carbide seed substrate supported by the supporting member being in a region other than a region where the metal carbide film has been formed.

11 : A silicon carbide substrate, obtained by slicing the silicon carbide ingot which has been obtained with the manufacturing method according to claim 10 ,
the substrate including a metal element forming the metal carbide film, a concentration of the metal element being not less than 0.01 ppm and not more than 0.1 ppm.

12 : A semiconductor device, comprising a silicon carbide substrate including at least one selected from the group of metal elements consisting of titanium, vanadium and zirconium, a concentration of the metal element being not less than 0.01 ppm and not more than 0.1 ppm.

13 : The semiconductor device according to claim 12 , wherein
the silicon carbide substrate is a semi-insulating substrate.

14 : The semiconductor device according to claim 12 , wherein
the silicon carbide substrate is an n type substrate.

15 : The semiconductor device according to claim 12 , wherein
the silicon carbide substrate is a p type substrate.

16 : A method of manufacturing a semiconductor device, comprising the steps of:
preparing the silicon carbide substrate according to claim 11 ; and processing the silicon carbide substrate.

Assignees

• Sumitomo Electric Industries

Inventors

• Sasaki Makoto

Classifications

• H10P14/3408

  Silicon carbide · CPC title

• H10P14/2904

  Silicon carbide · CPC title

• H10P14/36

  characterised by treatments done before the formation of the materials · CPC title

• H10P90/12

  Preparing bulk and homogeneous wafers · CPC title

• H10D12/032

  of vertical IGBTs · CPC title