Development of Low-Cost Thin-Film Polycrystalline Silicon Solar Cells for Terrestrial Applications.

摘要

This research program develops low-cost polycrystalline silicon solar cells suitable for large-scale terrestrial utilization. The treatment of molten metallurgical silicon with chemical reagents is effective for the preferential removal of aluminum;however,the concentration of iron is not appreciably lowered. The recrystallization of chemically treated metallurgical silicon on graphite substrates produces silicon sheets with relatively large crystallites. The electrical and structural properties of epitaxial silicon layers on recrystallized metallurgical silicon are investigated. Silicon solar cells are prepared by depositing the active region of the solar cell on recrystallized metallurgical silicon substrates using the thermal reduction of trichlorosilane containing appropriate dopants. At the present,the AMl efficiency is about 5% for large area (30sq cm) cells and is higher than 6% for smaller area (5sq cm) cells.