The original raw material is quartz sand.
Crystalline silicon materials (including polycrystalline silicon and monocrystalline silicon) is the most important photovoltaic materials, polysilicon production technology has long been in the United States, Japan, Germany and other 3 countries 7 companies in the hands of 10 factories, the formation of technology blockade, market monopoly situation.
Pure Silicon (SI) is extracted from the natural quartz ores (the main component of silica), and purification is a technology of high technology content.
1. Silica and carbon powders react at elevated temperatures to produce coarse silicon:
Sio2+2c==si (Coarse) +2co
2. The reaction of coarse silicon and chlorine to the formation of chlorinated silicon under high temperature conditions:
Si (Coarse) +2cl2==sicl4
3. Silicon chloride and hydrogen react under high temperature conditions to obtain pure silicon:
Sicl4+2h2==si (Pure) +4hcl
High purity silicon is extracted in quartz, taking monocrystalline silicon as an example, refining to undergo the following process: Quartz sand One metallurgy grade silicon one purification and refining one single crystalline silicon ingot a silicon wafer cutting.