PFM Study of Crystals with the Co-Existence of Ferroelastic and Ferroelectric Domains

Abstract

Piezoresponse force microscopy provides an efficient mean for the visualization of the domains with a nanoscale resolution. In this paper, PFM studies have been carried out on ferroelectric materials of special interest. Occurrence of both ferroelectric and ferroelastic properties in the same material is a unique phenomenon which can be used for numerous device fabrication. Bismuth Titanate and Lead Potassium Niobate are the ferroics studied here. Bismuth titanate has one of its crystallographic axes slightly tilted out of the plane resulting in a strong polarization component along the lateral direction. The surface and the phase plots, both along the vertical z-direction and on the x-y plane, have been captured and discussed. In the case of PKN ferroelectric b-axis and ferroelastic c-axis orthogonality relationship in bulk breaks down on the nanoscale observation.