Papers by Keyword: 4H Silicon Carbide

Abstract: Understanding the growth and propagation of defects in SiC remains of interest in an effort to continue to improve device performance. A post-growth boule heat-treatment revealed to form micropipe pairs from apparent single screw dislocations is reviewed. In the treated samples almost no 1c threading screw dislocations were found. Instead, micropipe pairs were observed in similar densities to 1c threading screw dislocations in non-heat treated samples. It is hypothesized that the elevated temperatures allowed for enhanced dislocation mobility, enabling the transition.

Abstract: Efforts to develop 150 mm 4H SiC bare wafer and epitaxial substrates for power electronic device applications have resulted in quality improvements, such that key metrics match or outperform 100 mm substrates. Total dislocation densities and threading screw dislocation densities measured for 150 mm wafers were ~4100 cm^-2 and ~100 cm^-2, respectively, compared with values of ~5900 cm^-2 and ~300 cm^-2 measured for 100 mm wafers. While median basal plane dislocation counts in 150 mm samples exceed those of the smaller platform, a nearly 45% reduction was realized, resulting in a median density of ~3900 cm^-2. Epilayers grown on 150 mm substrates likewise exhibit quality metrics that are comparable to 100 mm samples, with median thickness and doping sigma/mean values of 1.1% and 4.4%, respectively.