His current research interests are in the areas of the deposition and electro-optic properties of thin film materials, their application to photovoltaic devices, and scale up of promising technologies for manufacturing. He is currently working on thin-film materials and devices based on CdTe. He has built an advanced metal oxide deposition system for research into transparent conducting oxides (TCOs). He has prepared the entire CdTe solar cell front stack (TCO/HRT/window buffer) by hollow cathode sputtering in this machine. Since completing the machine in mid-2015 he has used it to prepare i-ZnO, ZnO:Al (AZO), ZnOxNy, Zn1-xMgxO, SnO2, ZnxSnyO, CdO, CdO:X, MoO3, NiO, Cu2O, CuOxNy, and CuAlO2. He is studying the influence of band offsets in heterojunction devices, stoichiometry and defects in CdTe, CdTe growth and alloying, transport in electronic materials, and the doping of transparent conducting oxides. He has collaborations with Rutgers University, University of Delaware, National Renewable Energy Laboratory, CTF Solar, Avancis, and CTIEC funding for his research is from China National Building Materials via China Triumph International Engineering Company.
