Evaluation of effective elastic constants for polycrystalline PZT thin films by XRD patterns and pole figures

Abstract

Polycrystalline PbZr_0.52Ti_0.48O₃ (PZT) thin films with different thicknesses were prepared by metal-organic decomposition (MOD) at different thermal decomposition temperatures, and their effective elastic constants were evaluated with X-ray diffraction (XRD) techniques. The relative intensities of textures in the thin films were analyzed from XRD patterns, and the effective elastic constants were calculated by averaging over orientations according to the relative intensities. On the other hand, Gaussian distribution functions were used to fit the normalized intensities of (001) pole figures, and the effective elastic constants of PZT thin films were calculated according to the grains’ orientation distribution described by Gaussian distribution functions. The results show that the effective elastic constants of PZT polycrystalline thin films evaluated by XRD patterns are in good agreement with those evaluated by pole figures, and the differences are within 10%. The effective elastic constants of PZT thin films are greatly affected by the thermal decomposition temperature, while the effects of thickness of thin films are relatively small.