Numerical analysis on the thermal stress and dislocation density of a 300 mm SiC single crystal grown by the PVT method

Abstract

The expansion of the diameter of a SiC single crystal to 300 mm represents a significant milestone in the technological development of SiC crystal growth. However, growing a 300-mm SiC crystal with the method of physical vapor transport (PVT) poses substantial challenges primarily owing to thermal stress and dislocation multiplication, both of which are intrinsically related to crystal quality. This study employs numerical simulations to investigate thermal stress, resolved shear stress (RSS) on the basal and prismatic planes, and the density of basal plane dislocations (BPDs) in a 300-mm SiC single crystal. Key factors such as the off-axis growth, high-temperature creep, and thermal stress relaxation are considered with comparison to those for a 200-mm SiC single crystal. The results indicate that prismatic slip and BPD density in a 300-mm SiC single crystal further increases.