Abstract: Microstructure, surface morphology and optical properties of ZnO thin film with 4at.% In doping concentration were measured by X-ray diffractometer, scanning electron microscope and UV-Vis spectrophotometer. Microstructure analysis shows that all films are polycrystalline and exhibit the hexagonal wurtzite structure. The crystallinity is deteriorated due to doping with indium. Intensity of the diffraction peaks almost has no change with annealing temperature increases. Surface morphology results indicate that the films are irregular, and possess the particle size of 50-100 nm having uniform and dense microstructure. Optical transmittance spectra show that as annealing temperature increases, the value of optical bandgap decreases from 3.267 to 3.197 eV, which might be induced by the transition of residual stress.

Key words: ZnO thin film;annealing temperature;optical properties