ZnO thin films epitaxially grown by electrochemical deposition method with constant current

The electrochemical deposition (ECD) method is well suited to the preparation of large area devices and has several advantages, although the deposited films have a crystallinity problem. A constant current deposition method was employed for preparation of ZnO thin films in this study, because it was expected that the growth rate of the films could be controlled by means of the current density. The intensity of X-ray diffraction (XRD) peaks, and the size and shape of grains of ZnO films grown on polycrystalline Au substrates were observed to depend on the cathodic current density. On the basis of those results, deposition of ZnO on a Pt layer epitaxially grown on c-sapphire was carried out. The results of ϕ-scan XRD measurements showed in-plane orientation in agreement with the in-plane direction of the Pt substrate layer, which suggests that the ZnO thin film was epitaxially grown by the ECD method.