Growth of p-type 4H-SiC single crystals by physical vapor transport using p-type SiC powder

Abstract

The Al doping stability of p-type SiC has always been a difficult problem in the growth of p-type SiC. In this study, a novel Al doping method was used to grow p-type SiC. p-Type 4H-SiC crystals were grown by a physical vapor transport (PVT) method using p-type SiC powder. p-Type SiC powder was synthesized by a self-propagating high-temperature synthesis method. The powder was observed under an optical microscope. Raman and XRD analysis results demonstrated that the synthesized SiC powder was mainly a 3C-SiC polytype. The Al content and binding mode of the p-type SiC powder were characterized by EDS and XPS, respectively. In addition, the differences between using p-type SiC powder and direct Al compound doping in the SiC powder region to grow p-type SiC crystals were studied. Results showed that the continuity of Al element doping using p-type SiC powder was much better than the doping method of placing an Al compound in the SiC powder region. Moreover, the utilization rate of the Al element was greatly increased. The resistivity of the crystal grown by the p-type SiC powder method was reduced by about 5 times. And the axial resistivity uniformity was also improved by the p-type SiC powder method.