| 摘要 |
PROBLEM TO BE SOLVED: To provide pretreatment for raw material silicon in the production of highly purified silicon for a solar cell and for a semiconductor, in which impurities included in the raw material silicon is beforehand efficiently removed, thus the improvement of the productivity of high purity silicon in a refining step as the poststage and the stabilization of the quality of the product are achieved. SOLUTION: Metal silicon as the raw material is pulverized into≤1 mm, is thereafter dispersed into an acid aqueous solution or a basic aqueous solution to form a slurry shape, and is subjected to leaching treatment at a leaching temperature of≥100°C under the pressurization of≥1 atom to remove impurities. Further, for more efficiently removing impurities, it is desirable that the pulverized raw material silicon is subjected to firing treatment at 1,000 to 1,400°C before performing the leaching treatment under pressurization. COPYRIGHT: (C)2011,JPO&INPIT
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