Separation and Recovery of Refined Si from Al–Si Melt by Modified Czochralski Method
Jingwei Li,
Juncheng Li,
Yinhe Lin,
Jian Shi,
Boyuan Ban,
Guicheng Liu,
Woochul Yang,
Jian Chen
Affiliations
Jingwei Li
Key Laboratory of Photovoltaic and Energy Conservation Materials, Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
Juncheng Li
School of Material Science and Engineering, Jiangsu University, Zhenjiang 212013, China
Yinhe Lin
School of Chemistry Engineering, Yangtze Normal University, Chongqing 408000, China
Jian Shi
Key Laboratory of Photovoltaic and Energy Conservation Materials, Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
Boyuan Ban
Key Laboratory of Photovoltaic and Energy Conservation Materials, Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
Guicheng Liu
Department of Physics, Dongguk University, Seoul 04620, Korea
Woochul Yang
Department of Physics, Dongguk University, Seoul 04620, Korea
Jian Chen
Key Laboratory of Photovoltaic and Energy Conservation Materials, Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
Separation of refined silicon from Al−Si melt is still a puzzle for the solvent refining process, resulting in considerable waste of acid and silicon powder. A novel modified Czochralski method within the Al−Si alloy is proposed. After the modified Czochralski process, a large amount of refined Si particles was enriched around the seed crystalline Si and separated from the Al−Si melt. As for the Al−28%Si with the pulling rate of 0.001 mm/min, the recovery of refined Si in the pulled-up alloy (PUA) sample is 21.5%, an improvement of 22% compared with the theoretical value, which is much larger 1.99 times than that in the remained alloy (RA) sample. The content of impurities in the PUA is much less than that in the RA sample, which indicates that the modified Czochralski method is effective to improve the removal fraction of impurities. The apparent segregation coefficients of boron (B) and phosphorus (P) in the PUA and RA samples were evaluated. These results demonstrate that the modified Czochralski method for the alloy system is an effective way to enrich and separate refined silicon from the Al−Si melt, which provide a potential and clean production of solar grade silicon (SoG-Si) for the future industrial application.