US 12,421,624 B2
SiC substrate, SiC epitaxial substrate, SiC ingot and production methods thereof
Tadaaki Kaneko, Hyogo (JP)
Assigned to KWANSEI GAKUIN EDUCATIONAL FOUNDATION, Hyogo (JP); and TOYOTA TSUSHO CORPORATION, Nagoya (JP)
Appl. No. 17/632,498
Filed by KWANSEI GAKUIN EDUCATIONAL FOUNDATION, Hyogo (JP); and TOYOTA TSUSHO CORPORATION, Nagoya (JP)
PCT Filed Aug. 5, 2020, PCT No. PCT/JP2020/030079
§ 371(c)(1), (2) Date Feb. 2, 2022,
PCT Pub. No. WO2021/025085, PCT Pub. Date Feb. 11, 2021.
Claims priority of application No. 2019-144544 (JP), filed on Aug. 6, 2019.
Prior Publication US 2022/0282395 A1, Sep. 8, 2022
Int. Cl. C30B 29/36 (2006.01); C30B 25/20 (2006.01); C30B 33/02 (2006.01); H01L 21/02 (2006.01)
CPC C30B 29/36 (2013.01) [C30B 25/20 (2013.01); C30B 33/02 (2013.01); H01L 21/02002 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A method for producing a SiC substrate comprising a heat treatment step of heat-treating a SiC base substrate in a SiC main container where the SiC base substrate and a SiC material composed of SiC face each other, and transporting a Si element and a C element in an internal space of the SiC main container,
wherein the heat treatment step includes two or more steps among the following steps (a), (b), and (c):
(a) a strained layer removal step of removing a strained layer of the SiC base substrate by transporting the Si element and the C element from the SiC base substrate to the SiC material to etch the SiC base substrate;
(b) a bunching removal step of removing macro step bunching on the SiC base substrate by heating the SiC base substrate under a SiC—Si equilibrium vapor pressure environment; and
(c) a basal plane dislocation reduction step of forming a SiC growth layer in which basal plane dislocation is reduced, on the SiC base substrate by heating the SiC base substrate under a SiC—C equilibrium vapor pressure environment and transporting the Si element and the C element from the SiC material to the SiC base substrate to perform crystal growth of the SiC base substrate.