Semiconductive lead zirconate titanate thin films grown by pulsed laser deposition

Abstract

Heterostructures consisting of PbZr0.2Ti0.8O3 epitaxial films on a SrTiO3 (100) substrate with a La0.67Sr0.33MnO3 bottom electrode were prepared by pulsed laser deposition. Plane-parallel capacitor structures were investigated by dielectric spectroscopy and piezoelectric measurement. Shift in a piezoelectric loop indicates that a sample has a small imprinted internal field, directed towards the copper top electrode. Temperature-dependent measurements in a range of 300–500 K were performed to obtain information on the frequency-depending response of the metal–ferroelectric–metal (MFM) structure and to analyze the effect of charge injection through the two Schottky-like contacts. The charge injection process greatly increases the conductivity in the low-frequency region.