IMPROVED METHODS AND APPARATUS FOR PRODUCING TRICHLORO-HYDROSILICON AND POLYSILICON

摘要

Improved methods and apparatus for producing trichlorosilane and polysilicon are provided. The improved methods include the method for producing trichlorosilane and the method for producing polysilicon. The method for producing polysilicon includes the method for producing trichlorosilane by chloro-hydrogenation, and it comprises: a) heating metallurgical silicon to 300-500°C in baking oven, and then feeding the metallurgical silicon into a reactor; b) vaporizing and heating silicon tetrachloride to form gaseous silicon tetrachloride at 160-600°C by an exterior heater; c) preheating hydrogen chloride to 150-300°C by an exterior heater; d) preheating hydrogen to 300-600°C by an exterior heater; and e) feeding gases obtained from steps b), c), and d) into the reactor, wherein the mole ratio of hydrogen to silicon tetrachloride is 1-5:1, the mole ratio of hydrogen chloride to silicon tetrachloride is 1:1-20, maintaining the temperature of the reactor at 400-600°C, and keeping the pressure of the reactor at 1.0-3.0MPa. Polysilicon, which is applicable to the industry of semiconductor and solar battery, can be produced with low cost and high efficiency by the present method.