SINGLE CRYSTAL SILICON CARBIDE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce a large-sized single crystal SiC of an ultrahigh quality free from the presence of residual impurities and micropipe defects, etc., with good productivity by minimizing contamination from the outside and effects of a fluctuation in atmosphere at the time of heat treatment. SOLUTION: Two composites M and M prepared by smoothly polishing the surfaces 2a of β-SiC (or α-SiC) polycrystal films 2 deposited on the surfaces of α-SiC single crystal substrates 1 according to a thermal chemical vapor deposition(CVD) method are brought into close contact and fixed through the mutual smooth polished surfaces 2a' and 2a' with the same crystal axis direction of the α-SiC single crystal substrates 1 and 1. In this state thereof, the composites M and M are heat-treated at a high temperature of >=2,000 deg.C in an atmosphere under the SiC saturated vapor pressure to thereby integrally grow a single crystal oriented in the same direction as the crystal axis of the α-SiC single crystal substrate 1 by the recrystallization of the β-SiC polycrystal films 2.