Temperature dependence of the conduction mechanisms through a Pb(Zr,Ti)O3 thin film

• La0.67Sr0.33MnO3 buffer layer is used in order to have a pure PbZr52Ti 0.48O3 perovskite phase on Pt(111).
• Below 270 K, leakage current is limited by charge injection through Schottky barrier.
• Above 270 K, bulk conduction with hopping mechanism occurs, possibly along grain boundaries.

The conduction mechanisms through a lead zirconate titanate (PZT) thin film grown by pulsed laser deposition with a La0.67Sr0.33MnO3 (LSMO) buffer layer on epitaxial Pt (111) were assessed in the 230–330 K temperature range. X-Ray diffraction and transmission electron microscopy evidenced a columnar growth of (001)- and (011)-oriented PZT grains. The leakage current through the Pt/PZT/LSMO/Pt structure was then systematically measured. From current vs. time curves, a threshold voltage was found below which stable and reproducible current values are obtained, thus avoiding resistance degradation. The conduction mechanism changes from interface controlled at low temperatures to bulk controlled around room temperature. The hopping-type conductivity evidenced above 270 K is consistent with the extended defects and columnar microstructure of the PZT film.