| abstract |
PROBLEM TO BE SOLVED: To provide a method for producing semiconductor grade polycrystalline silicon having a low carbon content. A method for producing high-purity polycrystalline silicon by reacting purified trichlorosilane with hydrogen, An activated carbon adsorption layer is provided in the circulation line for hydrogen supplied to the reaction system, and the methane concentration in the hydrogen gas supplied to the reaction system is controlled by limiting the methane concentration in the hydrogen gas passing through the adsorption layer to 10 ppm. Manufacturing method of high-purity polycrystalline silicon. |