Nanoindentation characterization of ZnO thin films

The effects of the indentation load, indentation-loading time and the creep behavior of 2–3 μm thick ZnO films deposited on a Si(1 0 0) substrate were investigated by nanoindentation. The ZnO thin films were deposited under different sputtering powers by a radio frequency magnetron sputtering system. The crystallographic and surface properties of the films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). Results showed that Young's modulus and the hardness of the films increased as the sputtering power was increased. The hardness and Young's modulus slightly decreased as the indentation rate and creep time were increased. The best ZnO film mechanical properties were found at a sputtering power of 225 W.