Analysis of sublimation growth of bulk SiC crystals in tantalum container

Sublimation growth of SiC bulk crystals in tantalum container is studied bo th experimentally and theoretically. The model of heterogeneous processes o ccurred on the side wall of the tantalum container proposed recently in Ram m et al. (Mat. Sci. Eng. B 61-62 (1999) 107) is extended to take into accou nt the process of carbon gettering by the container side wall. We formulate a quasi-steady approach for modeling of the bulk crystal growth. Using thi s concept we predict evolution of the crystal shape and study processes whi ch govern SiC bulk crystal growth. We apply anisotropic thermal elastic ana lysis to predict stress distribution in the growing crystal. For the first time a model of dislocation formation is applied for SiC bulk growth to com pute dislocation density field in highly stressed areas of the growing crys tal. (C) 2000 Published by Elsevier Science B.V. All rights reserved.