Effects of Raw Materials on the Growth of Silicon Carbide Single Crystal

SiC single crystal was grown by physical vapor transportation (PVT) technique using β-SiC raw materials. The phase transformation of raw materials during the crystal growth was investigated by XRD. It was found that the phase transition fromβ-SiC to α-SiC was completed after growth of 30min. The molar ratio of Si/C in the grown crystal was more than 1 and dependent on the growth time. The maximum value of Si/C was obtained at the intermediate growth process. The formation of pinhole in the grown crystal was related to the deviation from stoichiometry of Si/C=l in the vapor phase and the impurity of raw materials. It was confirmed by EDX analysis.