METHOD OF REFINING METALLURGICAL SILICON WITH DRY ARGON PLASMA WITH INJECTION OF WATER ONTO MELT SURFACE WITH SUBSEQUENT DIRECTED CRYSTALLISATION Russian patent published in 2012 - IPC C01B33/37 C30B29/06 C30B28/06 

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of purifying silicon using plasma technology during industrial production of silicon for photoelectronic industry, as well as for making solar panels. The method involves heating crude silicon in a crucible until a melt is obtained and treatment of the surface of the melt with a plasma jet, containing an inert gas, directed at an acute angle to the surface of the melt, wherein the crude silicon is heated and melted using resistive heaters in a vacuum in a rectangular quartz crucible, the bottom temperature of which controlled using an optical pyrometre, wherein the surface of the silicon melt is treated with a dry argon plasma jet, while simultaneously feeding onto said surface portions of distilled water with volume ranging from 0.01 to 0.05 cm³ at pressure 1000-1500 kgs/cm² through an injector nozzle, after which a polycrystalline silicon ingot is formed by controlled directed crystallisation.

EFFECT: obtaining from metallurgical silicon with purity of 98-99,9% a polycrystalline silicon ingot of purity 99,9999% with phosphorus content of not more than 0,1 ppmw, boron content of 0,1-1 ppmw, which is suitable for industrial production of photoconverters.