New Approach to Silicon Metallurgy

摘要

Much of the polycrystalline silicon in the world is produced by hydrogen reduction of trichlorosilane.The process is characterized by a low rate and low yield and requires high temperature and high hydrogen pressure.Moreover,trichlorosilane is produced by hydrogen reduction of tetrachlorosilane.The disadvantages of the hydrogen technology stimulated research of zinc metal-lothermy(zincothermy),SiCl4+2Zn->Si+2ZnCl2 at temperatures above the zinc boiling point(1180 K).The process has high productivity and high yield and can give silicon of apurity of 99.999999 and higher[1].