METHOD OF PURIFYING SILICON, SILICON PRODUCED BY THE METHOD AND SOLAR CELL

For silicon purification, first, silicon containing impurities together with purification additive (10) for removal of impurities is heated so that silicon is converted to molten form. The mixture is subjected to a step of reducing the amount of nonvolatile impurities while agitating so as to mix the purification additive (10) with the molten silicon (15), a step of reducing the amount of volatile impurities, and a step of dipping crystallization substrate (33) in the molten silicon (15) so that purified silicon (36) is crystallized on a surface of the crystallization substrate (33), thereby reducing the amount of impurities. The employment of these steps enables rendering large-scale purification facilities unnecessary and enables reducing energy loss attributed to repetition of melting and solidification of silicon and slug. As a result, purification of metallic silicon to a purity of about 7 N (nines) can be attained, and thus a silicon for solar cell can be provided with low cost.