Convective Flows during Crystal Growth in a Centrifuge

Abstract

Convective phenomena in the melt strongly influence crystal growth in a centrifuge. Large scale convective flows are induced, because hydrostatic equilibrium cannot be established in the melt, if the temperature gradient is not parallel to the “total” (gravitational plus centrifugal) acceleration. The convective velocity depends on parameters of the centrifuge and the furnace, as well as on the properties of the melt. A simple analytical expression for the convective velocity is obtained that includes the effect of both driving factors, the radial temperature gradient and the non-uniformity of the acceleration.