| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for purifying polycrystalline silicon capable of effectively abating or removing, from a polycrystalline silicon obtained by the zinc reduction method, various impurities such as granular quartz glass, boron-based impurities, metal impurities such as zinc, etc.SOLUTION: The method of the present invention for purifying polycrystalline silicon comprises: (A) a step of washing, with hydrochloric acid, an acicular or dendritic polycrystalline silicon manufactured by the zinc reduction method; (B) a step of washing, with water, the polycrystalline silicon washed at the step (A); (C) a step of drying the polycrystalline silicon washed at the step (B); (D) a step of washing, with hydrofluoric acid, the polycrystalline silicon dried at the step (C); (E) a step of washing, with water, the polycrystalline silicon washed at the step (D); and (F) a step of drying the polycrystalline silicon washed at the step (E). |
