Mechanisms of polarization switching in ferroelectric thin films

Abstract

The origin of the difference in the switching properties of ferroelectric thin films and bulk ferroelectrics is discussed. The ideas of the size effects which may account for this difference are critically reviewed. It is shown that the two often used models (the Janovec-Kay-Dunn surface nucleation size effect and the dielectric layer model) are irrelevant to the experimentally observed thickness dependence of the coercive field in the films. The surface pinning model and the depletion-assisted nearby electrode nucleation model are shown to be consistent with the experimental observations.