Method for forming and growing a single crystal of a semiconductor compound

Claim 1

A gradient zone freeze method for growing single crystal semiconductor compounds in a crucible having a seed well, a transition region and a main growth region the seed well containing a seed crystal to promote single crystal growth and the transition region and main growth region containing the polycrystalline form of the desired semiconductor single crystal comprising heating the crucible so as to melt the polycrystalline compound and to create and maintain a steep temperature gradient of from 80° to 200° C. in the region of the seed well, a lesser temperature gradient of from 50° to 150° C. in the transition region and a still smaller temperature gradient of from 5° to 50° C. in the main growth region, slowly cooling the crucible while maintaining the temperature gradients so as to induce crystal growth along a solid-liquid interface initially at the top of the seed crystal and which slowly rises through the transition region and up and through the main growth region.