Nonlinear current–voltage behavior in PZT thin films

In this paper, Pb(Zr0.52Ti0.48)O3 (PZT) thin films were prepared by sol–gel synthesis and characterized by X-ray diffraction, field emission scanning electron microscopy and current–voltage measurements. Here, we demonstrate that in addition to the outstanding ferroelectric and dielectric properties, the PZT films also have remarkably nonlinear current–voltage characteristics. Considering the contact of semi-conductive grains in the PZT films, a double Schottky barrier (DSB) model may be responsible for such phenomena. The test results show that with the decrease of annealing temperature and the increase of the film thickness, the threshold voltages (Vth) increase obviously. The maximum Vth value of 60.95 V and the minimum value of 6.9 V in our experiments were obtained from the five-layered samples annealed at 600 °C and the two-layered samples annealed at 700 °C, respectively. As a result, PZT thin film may lead to efficient switching and sensing devices.