Dielectric and ferroelectric response as a function of annealing temperature and film thickness of sol-gel deposited Pb(Zr_0.52Ti_0.48)O₃ thin film

We report the thickness and annealing temperature dependence of the structural, morphological, compositional, and electrical properties including ferroelectric characteristics of Pb(Zr_0.52Ti_0.48)O₃ thin films deposited by a sol-gel method. The thickness and annealing temperature of the films were in the range of 0.12–0.36 μm and 520–670 °C, respectively. The crystalline structure and growth behavior of the films have been studied by x-ray diffraction, scanning electron microscopy, and atomic force microscopy. It is demonstrated that the weak ac electric field dependence of the permittivity of the films in terms of the Rayleigh law can be explained. The coercive field obtained from a sweep up and down schedule of the capacitance-voltage curves is asymmetrical and shows different behavior according to the annealing temperature and thickness. We also show that the activation energy coefficient, γ, obtained from frequency dependent polarization-electric field hysteresis loops is related to the annealing temperature and thickness of the films. A low leakage current density (∼100 nA/cm² at 200 kV/cm) and low annealing temperature (∼520 °C) demonstrate the potential of the deposited films for integrated ferroelectric random access memory and piezoelectric sensor applications. © 1999 American Institute of Physics.