Preparation and characterization of CdSe thin film semiconductors, prepared by cathodic electrodeposition from an acid sulphate solution (CdSO4-SeO2) before and after thermal treatment in nitrogen atmosphere, were investigated. The effect of the bath temperature and how it affects the cadmium selenide (CdSe) deposits were studied. The formation of compact barrier layers of zinc blende CdSe was attained. Scanning electron microscopy and X-ray diffraction patterns present a remarkably intense cubic structure, even after thermal treatment. The Ni/CdSe/Au structure may exhibit rectifying properties depending on the temperature during the electrodeposition. Thermal annealing in nitrogen gas increases the conductivity of CdSe and intensifies the rectification properties of the Ni/CdSe/Au structure. (C) 2012 Elsevier B.V. All rights reserved.