摘要 |
Relatively pure Si (having less than about 1 ppm of detrimental impurities therein) is obtained from ordinary quartz sand by uniformly admixing such sand with suitable glass-forming materials, such as boron oxide and alkali-metal carbonates or oxides, melting such admixture to form a glass, annealing the glass so as to obtain a phase separation comprised of an SiO2- rich phase and an impurity-rich phase, extracting the impurity-rich phase via strong acid, such as nitric acid, washing and drying the remaining glass and reducing such glass with carbon-containing compounds, such as graphite, sucrose, starch, etc., in an electric arc. The so-obtained relatively pure silicon is suitable for fabrication into semiconductor components, such as solar cells.
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