Ferroelectric Properties of Pb(Zr 1−x Ti x )O 3 Graded Thin Films

Pb(Zr 1 m x Ti x )O 3 , PZT, thin films, with the composition changes continuously throughout the thickness of the films, have been synthesized using pulsed laser deposition process. Graded-structured PZT films, with PZT(25/75) on top layer and PZT(52/48) on bottom layer, exhibit markedly superior ferroelectric properties, whereas the double layer structured PZT films show pronouncedly inferior ferroelectric properties to uniform-compositioned PZT (52/48) films. The modification on ferroelectric properties of these graded PZT films is presumably due to the presence of film-to-substrate interfacial stress or layer-to-layer internal stress.