Nanoindentation and AFM characterization of lithium-doped ZnO sprayed thin films

In this work, structural, morphological and mechanical properties of Li doped ZnO thin films, grown on glass substrates using a chemical spray technique at different Li doping concentrations, were investigated. Besides, The structural properties of ZnO: Li thin films were characterized by means of X-ray diffraction. This analysis demonstrated that all films consisted of single phase ZnO and were well crystallized in wurtzite phase with the crystallites preferentially oriented towards (002) direction parallel to c-axis. Also we note that doping with lithium improve the crystalline quality of prepared thin films. The film surface morphology was analyzed by contact atomic force microscopy (AFM) in order to understand the influence of lithium doping on the surface roughness. AFM analysis shows an enhancement in the surface roughness of the doped ZnO: Li thin films. Finally, nanoindentation test was carried out to examine the mechanical properties of sprayed thin films such as the hardness and the Young's modulus. The mechanical properties of the ZnO: Li thin films were studied by the nanoindentation test. It was observed that the Li doping enhances the hardness and the Young's modulus.