In situ monitoring the growth of thin-film ZnS/Zn(S,O) bilayer on Cu-chalcopyrite for high performance thin film solar cells - Sáez-Araoz, R.; Abou-Ras, D.; Niesen, T.P.; Neisser, A.; Wilchelmi, K.; Lux-Steiner, M.Ch.; Ennaoui, A. (Thin Solid Films, 2009)