Physical origin of conduction in PZT thin films

Leakage conduction of Pt-Pb(ZrXTi:(1-X))O-3-Pt capacitors is studied by mea ns of different measuring techniques and analyzed in terms of semiconductor properties of the system. Based on the experimental data, it is concluded that two different regimes of carrier injection (with the critical electric field of the crossover between these regimes being independent of the meas uring technique) are responsible for true leakage conduction in Pt-Pb(ZrXTi 1-X)O-3-Pt films. For interpretation of the experimental results a Space-Ch arge-Influenced-Injection model which takes into account both role of charg e of depletion in the bulk of the film and injection through the blocking c ontact is proposed. This model describes well the main features of the obse rved current-voltage characteristics and provides a reasonable fit for the current-voltage curves measured at elevated temperatures, the values of the fitting parameters being in a good agreement with the results of other stu dies. The presented study provides insight in me physical nature of leakage conduction of Pt-Pb(ZrXTi1-X)O-3-Pt system and suggests a method for analy zing its semiconductor parameters by means of conduction measurements.