Abstract
High-quality ITO thin films were deposited onto different thicknesses of SiO2 buffer layer by Electron beam deposition technique at different substrate temperatures (200 - 325 degrees C). The effect of grain size (up to 13.5 nm) on the optical properties leads to decreasing both of reflectance and thermal emissivity and increasing the optical gap with decreasing the grain size of the films respectively.. The transmittance values are found to increase with increasing both the thickness of buffer layer and the substrate temperature. An average transmittance value of 92 % in the visible region and 83% in the near infrared (NIR) region of the spectrum and a resistivity value of 1.6x 10(-4) (Omega cm) are obtained. An increase in the band gap (3.08-3.54 eV) is observed by increasing the substrate temperature from 200 to 325 degrees C. The refractive index, extinction coefficient, Kubelka-Munk function and thermal emissivity of the thin films were determined and presented in this work.