Effect of post-deposition annealing on the properties of ZnO films obtained by high temperature, micro-controller based SILAR deposition

The ZnO thin films were prepared by successive ionic layer adsorption and reaction (SILAR) method at elevated precursor temperature. The films were later subjected to post-deposition annealing at different temperatures. This annealing process was found to be beneficial as it improved the structural and optical properties of the films. The ZnO films obtained by SILAR were found to be polycrystalline with hexagonal crystal structure. The crystallite size of the films increased considerably after annealing. The annealed films also showed very high absorption in UV region with marginal change in band gap. Both the crystallite size and optical absorbance were found to increase proportionately with the annealing temperature.