Investigation of properties thin films ZnO and SnO2 prepared with spray pyrolysis

We performed a comparative study of properties of the two oxides films ZnO and SnO₂ deposed by the spray pyrolysis technique prepared at 400 °C of deposition temperature and a deposition time equal to 10 min with the concentration of 0.1 mol/l, in order to optimize the precursor which allows having a high conductivity and high transmittance. Several techniques were used for the structural, morphological, optical and electrical characterization of the films. The characterization XRD showed that the SnO₂ film have cubic phase with preferential orientation (111) with a crystallite size equal to 57 * 10^-9 m. For the film of ZnO is polycrystalline in nature and the crystallite size at 12 * 10^-9 m. The transmittance is about 71 % for the films deposited with SnO₂ and around 81 % for films prepared ZnO these films confirms that it is possible to obtain good transparent; the gap value obtained at 3.83 eV for SnO₂ and 3.21 eV for ZnO. The refractive indexes were determined by ellipsometric measurements we have obtained values in the order of 2.304 and 2.146 for SnO₂ and ZnO films respectively. The measurement of the electrical resistivity also showed that the resistivity value of the ZnO thin film improved by over that of the SnO₂ film, is a remarkable result the use for photovoltaic applications.