%0 Journal Article
%A C.S Ganpule
%A V Nagarajan
%A H Li
%A A.S Ogale
%A D.E Steinhauer
%A S Aggarwal
%A E Williams
%A Ramamoorthy Ramesh
%A P De Wolf
%B Applied Physics Letters
%D 2000
%G eng
%I American Institute of Physics Inc.
%P 292-294
%R 10.1063/1.126954
%T Role of 90° domains in lead zirconate titanate thin films
%V 77
%X We report observations of the ferroelectric domain structure in epitaxial lead zirconate titanate (PbZr0.2Ti0.8O3) ferroelectric thin films using piezoresponse microscopy. By manipulating the film thickness, a uniform two-dimensional grid of 90° domains (a domains, i.e., c axis in the plane of the film) has been induced. Our studies show that the out of plane polarization direction in the film is preferentially oriented. 90° domains have been observed as regions of low piezoresponse, as compared to the fully c axis oriented regions. We have studied the influence of these 90° domains and the domain walls on the nucleation of polarization reversal. We observe that the nucleation occurs preferentially at 90° domain interfaces. Polarization reversal is seen to occur through the nucleation and subsequent growth of "semicircular/elliptical" reverse domains, which eventually consume the entire region as a function of reversal time. © 2000 American Institute of Physics.