Temperature dependent polarization switching properties of ferroelectric Pb_0.92La_0.08Zr_0.52Ti_0.48O _δ films grown on nickel foils

Ferroelectric Pb_0.92La_0.08Zr_0.52Ti _0.48O_δ films (≈2-μm thickness) were grown on LaNiO₃-buffered nickel foils by chemical solution deposition. Their ferroelectric and dielectric properties were measured as a function of temperature. With increasing temperature from room temperature to 200 °C, back-switching polarization increased while spontaneous polarization, remanent polarization, and coercive field decreased. The domain wall energy barrier was determined from the temperature-dependent back-switching polarization. Decreased irreversible/extrinsic and reversible/intrinsic dielectric responses were observed with increasing frequency. The ratio of irreversible to reversible contributions to dielectric nonlinearity was analyzed by the Rayleigh law. This ratio decreased with increasing frequency from 500 Hz to 500 kHz.