Evaluation of substrate material and Cu-doping effect on the microstructural and optical behavior of ZnO filmsFuchao Yang, Shuyi Ma, Xiaolei Zhang, Faming Li, Jing Liu and Qiang ZhaoEur. Phys. J. Appl. Phys., 62 1 (2013) 10302DOI: https://doi.org/10.1051/epjap/2013120248