The role of PbTiO3 layers in piezoelectric multilayer composite films based on Pb(Mg1/3Nb2/3)O3-PbTiO3

The sharp decrease of the remnant ferroelectric and piezoelectric properties of Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMNT) thin films close to the Morphotropic Phase Boundary (MPB) respect to their corresponding bulk ceramics is a major drawback for their integration in microdevices. In order to take full advantage of the excellent piezoelectric properties of polycrystalline PMNT in thin film form, a multilayer configuration with PbTiO3 (PT) layers is proposed. The PT layers generate an internal electric bias within the PMNT layer, which anchor an induced polarization in it. This results in a significant improvement of the piezoelectric behavior, obtaining remnant piezoelectric coefficients, d33 r, as high as 67 pm V− 1. The role of the thickness of the PT layers used is discussed, in order to find the optimum configuration for these multilayers.