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

The evolution of crystallization front and growth conditions during sublima tion growth of SiC bulk crystal is studied using a coupled heat and mass tr ansport two-dimensional model. It is shown, in particular, that movement of the inductor coil used far healing of the growth crucible modifies the tem perature 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 gen eration are applied for a detailed analysis of thermoelastic strain and dis location density evolution during SiC bulk crystal growth. An important eff ect of a method of SiC seed attachment to the holder is revealed by modelin g. It is shown that under optimal attachment? the maximum dislocation densi ty is concentrated near the crystallization front at the periphery of the c rystal. The region of high dislocation density expands with enlargement of the crystal. (C) 2000 Elsevier Science S.A. All rights reserved.