Method for manufacturing silicon carbide epitaxial substrate, and silicon carbide epitaxial substrate

Patent metadata

Field	Value
Publication number	US-2016355949-A1
Application number	US-201515114017-A
Country	US
Kind code	A1
Filing date	May 21, 2015
Priority date	Nov 12, 2014
Publication date	Dec 8, 2016
Grant date	—

Abstract

A method for manufacturing a silicon carbide epitaxial substrate includes: a step of placing a silicon carbide single crystal substrate within a chamber and reducing a pressure within the chamber; a step of increasing a temperature within the chamber to a first temperature; a step of introducing hydrogen gas into the chamber and adjusting the pressure within the chamber; a step of introducing hydrocarbon gas into the chamber; a substrate reforming step of increasing the temperature within the chamber to a second temperature and holding the temperature at the second temperature for a predetermined time, with the adjusted pressure within the chamber and a flow rate of the hydrogen gas being maintained and the hydrocarbon gas being introduced; and a step of growing an epitaxial layer on the silicon carbide single crystal substrate by introducing silane gas into the chamber with the second temperature being maintained.

First claim

1 . (canceled)

2 . (canceled)

3 . (canceled)

4 . (canceled)

5 . (canceled)

6 . (canceled)

7 . (canceled)

8 . A silicon carbide epitaxial substrate, comprising:
a silicon carbide single crystal substrate having a main surface inclined relative to a {0001} plane by more than or equal to 1° and less than or equal to 8° ; and an epitaxial layer formed on the silicon carbide single crystal substrate, in a surface of the epitaxial layer, trapezoidal defects, which are trapezoidal depressions, having a defect density of less than or equal to 1/cm 2 , the trapezoidal defects each including an upper base portion and a lower base portion intersecting with a <11-20> direction when viewed in plan view, the upper base portion having a width of more than or equal to 0.1 μm and less than or equal to 100 μm, the lower base portion having a width of more than or equal to 50 μm and less than or equal to 5000 μm, the upper base portion including a protruding portion, the lower base portion including a plurality of step bunchings.

9 . (canceled)

10 . The silicon carbide epitaxial substrate according to claim 8 , wherein the silicon carbide single crystal substrate has a diameter of more than or equal to 100 mm.

11 . The silicon carbide epitaxial substrate according to claim 8 , wherein the epitaxial layer has a thickness of more than or equal to 5 μm and less than or equal to 30 μm.

12 . A silicon carbide epitaxial substrate, comprising:
a silicon carbide single crystal substrate having a main surface inclined relative to a {0001} plane by more than or equal to 1° and less than or equal to 8° and having a diameter of more than or equal to 100 mm; and an epitaxial layer formed on the silicon carbide single crystal substrate and having a thickness of more than or equal to 5 μm and less than or equal to 30 μm, in a surface of the epitaxial layer, trapezoidal defects, which are trapezoidal depressions, having a defect density of less than or equal to 1/cm 2 , the trapezoidal defects each including an upper base portion and a lower base portion intersecting with a <11-20> direction when viewed in plan view, the upper base portion having a width of more than or equal to 0.1 μm and less than or equal to 100 μm, the lower base portion having a width of more than or equal to 50 μm and less than or equal to 5000 μm, the upper base portion including a protruding portion, the lower base portion including a plurality of step bunchings.

Assignees

• Sumitomo Electric Industries

Inventors

• Wada Keiji
• Nishiguchi Taro
• Genba Jun

Classifications

• H10P14/3408

  Silicon carbide · CPC title

• H10P14/2926

  Crystal orientations · CPC title

• H10P14/2904

  Silicon carbide · CPC title

• H10P14/24

  using chemical vapour deposition [CVD] · CPC title

• C30B25/14

  Feed and outlet means for the gases; Modifying the flow of the reactive gases · CPC title