METHOD FOR PRODUCING POLYCRYSTALLINE SILICON

The invention relates to metallurgy and/or chemistry, in particular to me thods and devices for producing a silicon tetrafluoride gas and polycrystall ine silicon from said silicon tetrafluoride gas. The method for producing si licon tetrafluoride from a hydrosilicofluoric acid solution consists in form ing, washing, drying and decomposing the acid extract and in bubbling a nons eparated silicon tetrafluoride and hydrogen fluoride flow through silicon di oxide. The silicon producing method consists in interacting the silicon tetr afluoride gas with magnesium vapour and in subsequently separating a final p roduct. Said invention makes it possible to produce a highly pure silicon, t o increase the final produce yield, to improve the environmental friendlines s of the production, to simplify the silicon production process and to reduc e the production cost of the final product.