On the Wurtzite-Type SiC Whiskers Obtained by Sublimation and the Thermal Stability of Basic SiC Polytypes,

摘要

2H-type SiC whiskers were obtained using the sublimation method. From the results of heating a powdered mixture of high-purity silicon and graphite,the thermal stability of basic SiC polytypes was discussed. The condlusions are summarized as follows: Beta-SiC crystals grow in the entire temperature range under conditions of high supersaturation;The initial phase which appears from heating Beta-SiC is mainly 6H above 1,600C and 4H or 2H below 1,400C; 2H, 3C,and 6H are stable in the range below 1,400C, 1,400-1,600C, 1,600-2,100C,and above 2,100C,respectively. 15R is unstable throughout the entire temperature range. (Author)