Three-dimensional simulation of facet formation and the coupled heat flow and segregation in Bridgman growth of oxide crystals

Three-dimensional (3D) simulation of facet formation and its coupled heat f low and segregation in the Bridgman growth of oxide crystals is presented. The growth of YAG crystals in the [1 1 1] direction, with {2 1 1} facets, i s taken as an example to illustrate the finite volume treatment of the inte rfacial kinetics involving supercooling and crystallographic constrains. Th e simulation successfully reveals experimental observations, and the growth conditions for reducing faceting are consistent with growth experience in general. Increasing thermal gradients or reducing interface convexity reduc es the faceting area. In addition, 3D convection and dopant segregation due to faceting are illustrated. The simulation also allows a different segreg ation coefficient at the facets, so that the abnormal segregation, such as the dark core, due to faceting can be simulated as well. (C) 2001 Elsevier Science B.V. All rights reserved.