Control of interface shape in the vertical bridgman-stockbarger technique

Abstract At very slow travel rates the solid-liquid interface shape (from the viewpoint of the solid) is convex when it lies within the heater and concave when it lies within the cooler. The dependence of interface position on travel rate, geometry of the ampoule, and on the relative temperatures of the heater and cooler increases as the effectiveness of heat transfer between ampoule and the surroundings diminishes and as the thermal conductivity of the material increases (at least for low travel rates).