Economic viability of a solar-grade silicon manufacturing process based upon plasma-arc refining

Abstract

The first polysilicon ingot manufactured using the plasma-arc process was fabricated into simple photovoltaic devices with 16% efficiency. A larger 250-mm ID reaction vessel was installed in the plasma-arc system, and initial process optimization experiments have resulted in an additional 1.79X reduction in the B-reduction half-life. Conversion of SG-Si production capacity from the Siemens process to plasma-arc processing would result in substantial capital and energy savings, completely eliminate the use of toxic Cl compounds and substantially reduce both solid and liquid waste produced. The fully-loaded production cost of SG-Si manufactured using this process is estimated at $11-13/kg.