manufacturing method of manufacturing methods and silicon tetrachloride of polysilicon

摘要

In Problems polysilicon manufacturing process, that can be used raw materials can be stably supplied at low cost, allowed to proceed smoothly chlorination reaction, impurities in the chlorination reaction after is suppressed, to produce energy efficient I to provide a process for the production of silicon tetrachloride and polysilicon can. A chlorination step of generating silicon tetrachloride by chlorination of granular material made up of carbonaceous material SOLUTION: A silicon dioxide reduction step to produce the poly-silicon by reduction with a reducing agent metal silicon tetrachloride and consists of an electrolytic process that produce chlorine gas and the reducing agent metal by molten salt electrolysis reducing agent metal chloride by-produced in the reduction step, the chlorination step, the carbon-containing material and silicon dioxide, oxygen gas coexistence It is intended to react them by supplying chlorine gas under, chlorinated chlorine gas is reused as a reducing agent of silicon tetrachloride by the reduction step the reducing agent metal produced in the electrolytic process, is generated by the electrolytic process wherein to be reused in the process.