Effect of Arsenic Doping in Polycrystalline Thin Film CdTe Solar Cells

Previous work has shown the positive effects of Arsenic doping in polycrystalline CdTe solar cells, particularly on charge carrier lifetimes, implied voltage due to the quasi Fermi level splitting, and improved device performance. In this study, we investigate the effect of varying arsenic concentrations, optimizing Cd vapor overpressure on the device performance. The devices were fabricated using a novel closed space sublimation method, in which, CdSeTe:As and CdTe:As would be sublimated under excess Cd vapor. Since CdSeTe is a material with a potential to achieve efficiency >25% cell efficiency, devices with the structure CdSeTe/ CdTe:As were fabricated and characterized.