Domain structures and piezoelectric properties in epitaxial Pb(Zr0.35,Ti0.65)O3 thin films

The ferroelastic twin-domain structures and piezoelectric properties were investigated in epitaxial Pb(Zr0.35,Ti0.65)O3 thin films with various c-domain volume fractions by metal organic chemical vapor deposition on (100)cSrRuO3∕(100)SrTiO3 substrates. The domain structures could be characterized into three regions: a-domain dominant, c-domain dominant, and their mixed domain regions. The mixed domain structure is quite unusual but formed a bilayer with two regions of different a∕c domain proportions: the bottom layer is the a1-a2 domain structure and top layer is the a-c domain structure. The films of the mixed region have attained largest piezoelectric coefficients, d33, presumably due to enhanced a-to-c domain switching.