Modeling for Mass Transfer and Thermal Stress of Silicon Carbide PVT Growth

The growth of SiC bulk crystal is studied using a physical model including chemical reactions, mass transfer and growth kinetics. The thermal stress distribution in an irregular shaped growing crystal is predicted using a two-dimensional anisotropic stress model. The growth and stress models are integrated into an existing global heat transport model to investigate variation of thermal field, growth rate and the shape of the as-grown crystal as well as the thermal stress distribution during a real time growth processes. The onset of dislocation is also correlated with thermal elastic stress qualitatively using the CRSS model. The simulated results are compared with experimental measurement. The effects of the growth system geometry are also discussed.