METHOD FOR PURIFICATION OF SILICON, SILICON, AND SOLAR CELL

摘要

Disclosed is a method for the purification of silicon, which can reduce the content of boron (that is contained as an impurity) in the purification of metal silicon to produce silicon suitable for use in a solar cell. Specifically disclosed is a method for the purification of silicon, which comprises the steps of providing a mixture having molten silicon and a molten salt co-present therein, introducing a gas containing a chlorine atom into the mixture, and introducing water vapor together with a gas containing a chlorine atom. The gas containing a chlorine atom is preferably chlorine gas or silicon tetrachloride. The molten salt is preferably a mixture of at least silicon dioxide and calcium oxide and may contain calcium fluoride.