METHOD AND APPARATUS FOR PURIFYING SILICON

PROBLEM TO BE SOLVED: To provide a method of purifying silicon, which uses a hollow rotary cooling body and enables silicon to be continuously purified in the atmospheric environment. SOLUTION: The method comprises a melt process of converting raw material silicon into molten silicon by heating; the first purification process of forming slag having a specific gravity smaller than that of the molten silicon in a molten state by bringing the molten silicon into contact with an additive; a soaking process of soaking the hollow rotary cooling body into a covered state of the molten silicon where at least a part of the molten metal face of the molten silicon is covered with the slag; and the second purification process of crystallizing solid silicon on the outer peripheral face of the cooling body by flowing a cooling fluid into a hollow part of the cooling body in the state of rotating the cooling body. COPYRIGHT: (C)2009,JPO&INPIT