Principle and Research Progress on Preparation Solar Grade (SoG) Silicon by Metallurgical Route
With ever-increasing need in photovoltaic industry,the shortage of silicon feedstock which can meet technical and economic specifications of the photovoltaic cells is severe.More and more attentions have been paid to the research of producing solar grade silicon by refining metallurgical grade silicon.The development status and trend of the world photovoltaic industry are reviewed and the process for obtaining polycrystalline solar-grade silicon by chemical and metallurgical routes are contrastively analyzd.The technology principles of solar grade silicon prepared by metallurgical routes along with conventional purification techniques are emphatically introduced.Meanwhile,the low cost technology for manufacturing solar grade multicrystal silicon is introduced and it is pointed out that the metallurgical method maybe the future research direction for purifying multicrystal silicon.