Mixed ternary heterojunction solar cell

摘要

A thin film heterojunction solar cell and a method of making it has a p-type layer of mixed ternary I-III-VI2 semiconductor material in contact with an n-type layer of mixed binary II-VI semiconductor material. The p-type semiconductor material includes a low resistivity copper-rich region adjacent the back metal contact of the cell and a composition gradient providing a minority carrier mirror that improves the photovoltaic performance of the cell. The p-type semiconductor material preferably is CuInGaSe2 or CuIn(SSe)2.