The effect of temperature and heating period on optical properties of ZnO nano layers deposited on LiNbO3

In this work، the optical properties of ZnO thin films were investigated experimentally. Zinc was sputtered by the magnetron sputtering method on the LiNbO3 crystal (as substrate)، followed by a thermal oxidation at 450oC of the obtained ZnO films. The variations of the transmittance، reflectance، and extinction coefficient were measured for temperatures (450-800 oC) and different periods of heating (15-120min) which were employed to study their effects on the optical characteristics of the ZnO samples. The optical band gap energy was determined and it showed reduction with temperature and an increase at 800 oC with period of heating.