Patent ID: 6887448
Filing Date: 2005-05-03
Classification: C01B,H01L,Y02E,Y02P

Abstract:
1. A method for producing high-purity silicon, characterized by the following steps: a) reaction of metallic silicon with silicon tetrachloride (SiCl b) removal of impurities from the resultant of trichlorosilane containing feed gas stream by scrubbing with condensed chlorosilanes at a pressure of 25 to 40 bar and a temperature from 160 to 220° C. in a multi-stage distillation column, to give a purified trchlorosilane containing feed gas stream and a solid containing chlorosilane suspension, and distillative separation of the purified feed gas stream into a partial stream essentially comprising SiCl c) disproportionation of the SiHCl d) thermal decomposition of the SiH