Resistivity Increase in 6H-SiC Crystal Grown with Simple Modification in PVT Process

Abstract

6H-SiC single crystal was grown with simple modification in PVT process to investigate the aspect of resistivity change in crystal. The modified process consisted of a new initial step to get rid of impurities in the growth cell before the main growth of SiC crystal. The new step in the modified process was designed to consist of higher temperature than the growth temperature for sublimation of impurities. SiC crystal grown with using 2 times of impurities sublimation process (ISP) step exhibited lower variation of resistivity value on whole wafer than SiC grown using with 1 time. With implementation of new modified step in growth process, SiC single crystal with resistivity value above 103Ωcm could be obtained by simple PVT process and conventional low-purity SiC source material.