Frequency-independent coercive field in Pb(Zr0.52Ti0.48)O3 polycrystalline thin film based on sol-gel synthesis

We investigated the structural and electrical properties of Pb(Zr0.52Ti0.48)O3 thin film using sol-gel spin coating method. The crystalline, structural, compositional, and morphological features of Pb(Zr0.52Ti0.48)O3 film were studied by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy, and atomic force microscopy, respectively. The relationship between the coercive field (Ec) and frequency (f) is a simple power-law, Ec(f) ∝ fβ, where β is the frequency coefficient. The β is zero in the Pb(Zr0.52Ti0.48)O3 capacitor, indicating the coercive field independence of frequency. This result may be attributed to Pb(Zr0.52Ti0.48)O3 thin film possessing the morphotropic phase boundary (MPB) with the coexistence of the tetragonal and rhombohedral phases. The MPB can reduce the domain wall energy to minimize the domain wall movement, and thus decreasing the resistance force acting on the domains.