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http://dx.doi.org/10.7844/kirr.2021.30.4.20

Removal of Fe from Metallurgical Grade Si by Directional Solidification  

Sakong, Seong-Dae (GRM)
Son, Injoon (School of Materials Science and Engineering, Kyungpook National University)
Sohn, Ho-Sang (School of Materials Science and Engineering, Kyungpook National University)
Publication Information
Resources Recycling / v.30, no.4, 2021 , pp. 20-26 More about this Journal
Abstract
Solar grade silicon (SoG-Si) has been commercially supplied mainly from off-grade high-purity silicon manufactured for electronic-grade Si (EG-Si). Therefore, for wider application of solar cells, the development of a refining process at a considerably lower cost is required. The most cost-effective and direct approach for producing SoG-Si is to purify and upgrade metallurgical-grade Si (MG-Si). In this study, directional solidification of molten MG-Si was conducted in a high-frequency induction furnace to remove iron from molten Si. The experimental conditions and results were also discussed with respect to the effective segregation coefficient, Scheil equation, and Peclet number. The study showed that when the descent velocity of the specimen decreased, the macro segregations of impurities and ingot purities increased. These results were derived from the decrease in the effective segregation coefficient with the decrease in the rate of descent of the specimen.
Keywords
solar cell; metallurgical grade silicon; directional solidification; iron; effective segregation coefficient;
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Times Cited By KSCI : 2  (Citation Analysis)
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