Effect of annealing temperature on structural, optical and electrical properties of zinc oxide (ZnO) thin films deposited by spray pyrolysis technique

In the present paper, the structural, optical and electrical properties of zinc oxide thin films were studied before and after annealing temperature at 500 degrees C. The ZnO thin films were sprayed on glass substrates at 350 degrees C, which were heated using the solar cells method. Polycrystalline films with a hexagonal wurtzite structure with (002)preferential orientation corresponding to ZnO films were observed. It can be found that the good crystallinity are achieved in the films annealed at 500 degrees C. All films exhibit an average optical transmittance about 95% measured by UV vis analyzer. The shift of optical transmittance towards high wavelength can be showed by the increases of band gap after annealing temperature which can be explain by the oxygen diffusion with annealing temperature. The electrical resistivity measured of our films in the order 0.4 (Omega. cm). (C) 2015 Elsevier GmbH. All rights reserved.