In situ synchrotron x-ray diffraction study of electrical field induced fatigue in Pt/PbZr0.45Ti0.55O3/Pt ferroelectric capacitors

Abstract

Highly brilliant synchrotron x-ray radiation was used to measure in situ the microstructural response of a ferroelectric capacitor subjected to bipolar rectangular pulses. High-resolution x-ray diffraction experiments were performed on a (111)-oriented PbZr0.45Ti0.55O3 thin film with a composition in the morphotropic region and sandwiched between two platinum electrodes. From original real time measurements, the microstructural changes with electrical cycling have been evidenced and correlated with the observed polarization fatigue measured during the x-ray diffraction experiment. From concomitant variations of the diffracted intensity and the switching current maximum, several mechanisms have been discussed as a possible origin of the polarization fatigue: field induced phase transformation, oxygen vacancy self-ordering and widening of the internal bulk screening field distribution function during cyclic switching. © 2005 IOP Publishing Ltd.