METHOD OF PURIFICATION OF SILICON

摘要

Method of purification of technical silicon based on dissolving -crystallization in alloys of fusible metals comprises three stages: two (preparatory and finishing) - removal of impurities and one removal of atoms of metal-solvent. In preparatory stage a load of technical silicon is added periodically into alloy of fusible metal, the alloy is mixed in a vacuum by an impulse scavenge with an inert gas, and silicon is crystallized in the shape of tabular silicon crystals. In the finishing stage loads of tabular silicon crystals are added into the other alloy of fusible metal, the alloy saturated with silicon is transported to the crystallization zone wherein silicon is grown in the shape of a block on a silicon plate. Removal of atoms of fusible metals is achieved by application of direct crystallization method, when monocrystals of silicon are grown from blocks of silicon that were obtained in the finishing stage.