Effect of carrier concentration of ZnO layer for the visible-light transparent solar cells performance

Abstract

Visible-light transparent solar cells based on heterojunction of NiO and ZnO layer that absorbs only ultraviolet light were fabricated. The oxygen vacancy, which is the one of the origin of free carrier of ZnO, becomes a defect works as a recombination center in ZnO near the pn interface. In this study, we varied the Ar-O₂ gas supply ratio f(O₂) [f(O₂) = O₂/(Ar+O₂)] during ZnO sputtering to reduce defects in ZnO near the pn interface.