METHOD AND APPARATUS FOR MANUFACTURING POLYCRYSTALLINE SILICON

摘要

PROBLEM TO BE SOLVED: To replenish zinc while suppressing mixing of impurities in a method and an apparatus for manufacturing polycrystalline silicon, comprising taking out zinc by the electrolysis of zinc chloride formed by the reduction of silicon tetrachloride and then reusing the taken-out zinc for the reduction of silicon tetrachloride. SOLUTION: The apparatus 1 for manufacturing polycrystalline silicon comprises: a vaporization device 5 for forming zinc gas G1 by heating solid zinc B1; a vaporization device 6 for forming zinc gas G2 by heating zinc melt L2; a reaction furnace 2 for forming polycrystalline silicon and zinc chloride gas G4 by reducing silicon tetrachloride gas G3 by either the zinc gas G1 or G2; and an electrolyzing device 4 for forming the zinc melt L2 by electrolyzing zinc chloride melt L1 obtained by liquefying the zinc chloride gas G4 and feeding the zinc melt L2 to the vaporization device 6. Piping 12 extending from the vaporization device 6 is provided with a check valve 19 for preventing inflow of the zinc gas G1. COPYRIGHT: (C)2008,JPO&INPIT