The microstructure behavior of the TiO2/ZnO bilayer films using x-ray diffraction analysis

Abstract

In this research, we have attempted to accurately investigate the corresponding quantities of the structure, including the phase percent, the lattice constants, and the microstructure, including the size and shape of the crystallites, and the strain of the lattice corresponding to each layer of the multilayer structure. For this purpose, two well-known transparent oxide films i.e. TiO2 and ZnO have been grown on the glass substrate, respectively, and then annealed at temperatures between 400 and 550 °C. The structure and microstructure quantities of ZnO/TiO2 bilayers have been calculated using the x-ray diffraction analysis and Rietveld refinement method. The Rietveld results have demonstrated the presence of two distinct components of ZnO with the wurtzite structure and a component for TiO2 with the anatase structure. These results have indicated that annealing temperature plays an important role in controlling the percentage of phase, size and shape of crystallites, but does not have any essential influence on the variation of microstrain. Finally, the results obtained from Rietveld method have been compared with those obtained by scanning electron microscope images.