Self-diffusion of 12 C and 13 C in intrinsic 4H-SiC

The study of self-diffusion of carbon (12C and 13C) in low-doped (intrinsic) 4H-SiC using secondary ion mass spectroscopy (SIMS) was presented. A two layer 13C enriched structure with 13C/12C ratios of 0.01 and 0.1, respectively, was prepared by using vapor phase epitaxy. The subsequent anneals were carried out in Ar atmosphere in a rf heated furnace between 2100 and 2350°C for 15 min-40 h. A small variation in the enriched 13C concentration and in the layer thickness over the wafer was also presented.