Eddy Current Determination of Semiconductor Liquid-Solid Interface Location and Shape

Abstract

The vertical Bridgman method is a widely used technique for the growth of semiconductor single crystals from the melt [1–5]. In this method, a vertical multizone furnace is used to establish an optimized axial temperature gradient through which is translated an ampoule containing the liquid semiconductor. As the lower tip of the ampoule enters the furnace cold zone, single crystal solid is nucleated and a liquid-solid interface propagates upward through the ampoule. Today, the yield and quality of material grown by this technique is maximized by empirically optimizing the temperature gradient and the axial translation rate for each material system. Essentially, this involves repeated experimentation until a satisfactory material can be grown. Once obtained, temperature set points within the furnace, and furnace translation rate schedules are fixed from run to run.