Degradation Mechanism due to Water Ingress Effect on the Top Contact of Cu(In,Ga)Se2 Solar Cells

In this contribution, we present preliminary results on the change in CIGS solar cells behavior due to water ingress on the top contact. The impact of the top contact fabrication conditions was studied. Depending on these conditions, no change was observed on the ITO layer itself and an overall loss in device performance was observed after such exposure, mostly due to a decrease in fill factor. To identify the potential sources of degradation, thin film analysis and current-voltage (J-V) and quantum efficiency (QE) measurements on completed devices and hall effect measurement on window layer were performed to characterize the electrical properties.