Determination of the optical band gap and refractive index the sputtered ITO thin film, a promising device in solar-cell industry

High-quality indium–tin–oxide (ITO) thin film has been grown by the RF magnetron sputtering method on glass substrates without a postdeposition annealing treatment. The measured value of planar electrical resistivity electrical conductivity of the film, determined by 4-point probes method, is 29 Ohms/sq. The optical transmittance and reflectance spectrum of the film have been recorded in the wavelength range 200-2000 nm. The optical band gap and refractive index have been evaluated using available theories. The Eg is 3.75eV that has good agreement with other works. Moreover, an approach was employed to calculate thin film thickness which was obtained 238.4 nm, having agreement with experimental data from profilometry method.