Recent Developments of Numerical Calculation in Crystal Growth of SiC

Abstract

The eŠect of nitrogen and aluminum as doped impurities on the stability of SiC polytypes (Cor Si face 4H and 6H substrates) formed by physical vapor transport (PVT) was investigated. The stability of the polytypes was analyzed using classical thermodynamic nucleation theory with numerical results obtained from a global model including heat, mass and species transfer in a PVT furnace. The results reveal that the formation of 4H SiC was more stable than that of 6H SiC when a grown crystal was doped with nitrogen using C face 4Hand 6H SiC as seed crystals. In contrast, formation of 6H SiC was favored over 4H SiC when Si face 4Hand 6H SiC seed crystals were used. Meanwhile, the formation of 4H SiC was more stable than that of 6H SiC when aluminum was the dopant and Cand Si faces of 6H SiC were used as seed crystals. 6H SiC was preferred to grow rather than 4H SiC in the cases of C and Si faces of 4H SiC as seed crystals.