Evolution of thermoelastic strain and dislocation density during sublimation growth of silicon carbide

Abstract

Abstract The evolution of crystallization front and growth conditions during sublimation growth of SiC bulk crystal is studied using a coupled heat and mass transport two-dimensional model. It is shown, in particular, that movement of the inductor coil used for heating of the growth crucible modifies the temperature profile at the growth surface but can have no remarkable effect on the growth rate. Anisotropic elasticity theory and a semi-empirical model of dislocation generation are applied for a detailed analysis of thermoelastic strain and dislocation density evolution during SiC bulk crystal growth. An important effect of a method of SiC seed attachment to the holder is revealed by modeling. It is shown that under optimal attachment, the maximum dislocation density is concentrated near the crystallization front at the periphery of the crystal. The region of high dislocation density expands with enlargement of the crystal.