In this work, Tin-doped Indium oxide (ITO) thin films with thickness of 200 nm were grown on glass substrate kept at 100oC by electron beam evaporation method. Then the films were annealed at 300,400 and 500 oC, for 1 h. The effect of the annealing temperature on the structural and optical properties of the synthesized ITO thin films were studied by X-ray diffraction (XRD), scanning electron microscope (SEM), and spectral transmittance measurements. XRD pattern showed that increasing annealing temperature increased the crystallinity of thin films and at 500 ᵒC high quality crystalline thin films was obtained. The SEM images were also confirmed previous results. High transparency about 85% over the NIR and 80% over the visible wavelength region of spectrum were obtained at 500 oC. Band gap widening due to increase in annealing temperature was observed.
