METHOD FOR PRODUCING POLYCRYSTALLINE SILICON FROM HUDROSILICONFLUORIC ACID SOLUTION AND A PLANT FOR THE PRODUCING SILICON TETRAFLUORIDE AND POLYCRYSTALLINE SILICON

摘要

The invention relates to metallurgy and/or chemistry, in particular to methods and devices for producing a silicon tetrafluoride gas and polycrystalline silicon from said silicon tetrafluoride gas. The method for producing silicon tetrafluoride from a hydrosilicofluoric acid solution consists in forming, washing, drying and decomposing the acid extract and in bubbling a nonseparated silicon tetrafluoride and hydrogen fluoride flow through silicon dioxide. The silicon producing method consists in interacting the silicon tetrafluoride gas with magnesium vapour and in subsequently separating a final product. Said invention makes it possible to produce a highly pure silicon, to increase the final produce yield, to improve the environmental friendliness of the production, to simplify the silicon production process and to reduce the production cost of the final product.