| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for refining a silicon raw material capable of removing efficiently boron and other impurities from the silicon raw material having comparatively low purity, performing continuous processing, and performing mass production with a compact device constitution. <P>SOLUTION: The powder 1 of silicon or silica which is a raw material is dropped to thereby make the powder pass a high-temperature region 8 containing ozone. Boron contained in the powder is oxidized by ozone in the high-temperature region, and vaporized and removed as an oxide. The powder passing the high-temperature region 8 is cooled and recovered as powder from which boron is removed. The high-temperature region 8 is formed by high frequency induction thermal plasma or laser beam irradiation. Furthermore, the powder from which boron is removed is made to pass a high-temperature region 28 containing hydrogen to thereby reduce a silicon dioxide component contained in the powder by hydrogen in the high-temperature region to form silicon. <P>COPYRIGHT: (C)2012,JPO&INPIT |
