A method of processing a semiconductor assembly is presented. The method includes fabricating a photovoltaic module including a semiconductor assembly. The fabrication step includes performing an efficiency enhancement treatment on the semiconductor assembly, wherein the efficiency enhancement treatment includes light soaking the semiconductor assembly, and heating the semiconductor assembly. The semiconductor assembly includes a window layer having an average thickness less than about 80 nanometers, wherein the window layer includes cadmium and sulfur. A related system is also presented.