Purification and particle size control of b-SiC powder using thermocycling process

Recently, SiC single crystal growth has been of interest for the development of an alternative semiconducting material. The aim of this study was to purify and grow b-SiC particles for use as a single crystal source. First, a β-SiC powder with a particle size of about 10 mm and a purity of 99?5% was prepared from a phenyl-containing silica sol. Then, three different of heat treatment process were applied to grow the β-SiC particles and evaluate the effects of heat-treatment time and temperature. After three thermocycling processes carried out from 1850 to 2000°C in 1 h, the b-SiC particles had diameters over 100 mm because of a vaporisation-recrystallisation process that accelerated the b-SiC particle growth. Moreover, the thermocycling process improved the purity of b-SiC by eliminating metallic impurities.