XRD, SEM and photoelectrochemical examinations of deposits formed on the Cu substrate by electrochemical deposition in a water solution containing 0.2 mol dm(-3) of ZnSO4 and 0.002 mol dm(-3) of H2SeO3 were performed. Formation of Cu2Sex at potentials positive to that of electrochemical deposition of ZnSe was proved by the XRD technique. The formation of Cu2Sex continued even after deposition due to further diffusion of the deposited Se into Cu. A nano-crystalline ZnSe of cubic structure was electrodeposited at a potential of -0.62 V vs. Ag/AgCl electrode and XRD examination of deposits formed using cyclic potential scanning and pulse plating revealed the presence of hexagonal ZnSe along with the cubic one. A photoelectrochemical characterization proved that the electrodeposited ZnSe was a p-type semiconductor. A significant amount of Cu2Sex was formed during annealing of ZnSe electrodeposited on the Cu substrate although only traces of copper selenide were detected before the annealing. ZnSe, SnSe and a small quantity of Cu2Sex were detected by XRD after annealing of ZnSe electrodeposited on the Cu-Sn/Mo/glass substrate. (C) 2012 Elsevier Ltd. All rights reserved.