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.