Optical and structural properties of ZnSxSe1−x thin films deposited by thermal evaporation M. Ashraf, S. M.J. Akhtar, M. Mehmood and A. Qayyum Eur. Phys. J. Appl. Phys., 48 1 (2009) 10501 Published online: 04 July 2009 DOI: 10.1051/epjap/2009114