Optical characterization and γ-irradiation response of conductive transparent oxide of SnO2:Sb films

We are concerned in synthesizing conductive transparent oxide (CTO) films by spray pyrolysis deposition (SPD) for SnO2 (undoped) and SnO2:Sb (doped) film. The average value of the optical energy gap for CTO films of SnO2 and SnO2:Sb were found 4.01and 3.92 eV, respectively for direct transition before gamma irradiation. The optical conductivity of undoped and doped CTO film was calculated 8 x 10(14) and 24 x 10(14) Omega(-1) cm(-1), respectively. The average value of refractive index for SnO2 and SnO2:Sb films was found 1.93 and 1.67, respectively at 0.0 kGy. The average value of refractive index of annealed SnO2:Sb films was decreased from 2.07 to 1.55 after gamma-irradiation (22.0 kGy). The values of real part for the thermal annealed SnO2:Sb films were found positive before and after.-irradiation in Vis-NIR range; accordingly the thin film material is said to have an intrinsically capacitive optical response. The imaginary part values of annealed SnO2:Sb film were decreased after gamma-irradiation (22.0 kGy) in Vis-NIR range but still have positive value; so the material is said to have a resistive optical response. The optimum contact angle of doped CTO films was found 30 degrees with hydrophilic surface. This property of CTO could be applied as covers for solar cells and other devices to keep its efficiency during rains and high humidity.