Effects of Novel In+RbF Post-Deposition Treatment on Cu(In_xGa_1-x)Se₂ Solar Cells

Alkali halide post-deposition treatment (PDT) has been shown to improve Cu(In x Ga 1-x )Se 2 (CIGS) photovoltaic devices. In this study temperature-dependent current-voltage (JVT) experiments were used to evaluate a novel PDT performed by co-evaporating indium and RbF under a sulphur atmosphere. Three devices, one as-deposited, one with RbF PDT, and one with In+RbF PDT, were deposited by a three stage co-evaporation process.JVT results suggest the In+RbF PDT increased Voc and efficiency over the other treatments. It was also observed that the recombination rate was decreased and the ideality factor improved which may explain the improvements in V OC .