The Synthesis of Large-size Silicon Carbide Powder for Crystal Growth

A study on the synthesis of SiC powder with large size was presented. Special attentions were paid to synthetic temperature and ratio of large and small size silicon powder. Several experiments were designed to understand the effects of these conditions on phase composition, grain size and yield of SiC powder material by using a NAURA Advanced Physical Vapor Transport (PVT) System. It was found that high-quality SiC powder could be acquired at 1950°C for 10h. The rising proportion of large size silicon powder with 500~800μm was beneficial to synthesize large size SiC powder of >750μm. The results showed successful preparation of large size SiC powder and a significant reduction of carbon inclusions in SiC ingots by using SiC powder with large size.