Fabrication and properties of nanocrystalline zinc oxide thin film prepared by sol-gel method

Zinc oxide (ZnO) thin films were prepared on glass substrate by sol-gel dip-coating method. The structural properties were investigated by x-ray diffraction (XRD) method and atomic force microscope (AFM). The optical properties were measured by UV-Vis spectrophotometer. The XRD patterns showed that the films formed preferred orientation along c-axis which increased as a function of polyvinyl pyrrolidone (PVP) concentration. The films gave the crystallite size of 15-18 nm calculated by Scherrer s formula and grain size of 48-70 nm measured by AFM at different PVP concentrations. The direct optical band gap of the films was in the range of 3.80-4.08 eV.