Cu(In,Ga)Se2 thin films and devices sputtered from a single target without additional selenization

Typically, Cu(In,Ga)Se2 (CIGS) thin films for photovoltaic devices are deposited by co-evaporation or, alternately, by deposition of the metals with or followed by treatment in a selenium environment. In this article, we describe CIGS films that are instead deposited by RF magnetron sputtering from a single quaternary target without any additional selenization. Devices built with these films exhibit efficiencies as high as 8.9%. We demonstrate that deposition power can be varied in order to change the film morphology and improve device performance.