In this study, ZnO thin films have been deposited onto monocrystalline n-type Si(1 0 0) by electrodeposition at different applied potentials. XRD shows a preferential orientation (0 0 0 2) that increases when the applied cathodic potential increases. The XPS analysis presents a Zn/O composition close to stoichiometric. SEM micrographs show a compact structure with localized platelets with a grain size of about 10 mum. However, crystallite size determined by the Scherrer method shows a size close to 2.50 x 10(-2) mum, then the grains can be considered as clusters of crystallites. Optical measurements were made on samples deposited on ITO/glass through the same procedures giving a band gap of 3.3 eV in agreement with the reported values for ZnO at room temperature.