In-plane dielectric properties of epitaxial 0.65Pb(Mg[sub ⅓]Nb[sub ⅔])O₃-0.35 PbTiO₃ thin films in a very wide frequency range

Abstract

The in-plane dielectric properties of epitaxial 0.65Pb(Mg[sub ⅓]Nb[sub ⅔]O₃−0.35 PbTiO₃ thin films deposited on MgO by pulsed-laser ablation were determined over a wide frequency range and compared with single crystals and ceramics. Depressed values of the dielectric constant, induced diffused phase transition, dielectric relaxation, and nonlinear behaviors were observed in the films. The overall dielectric behaviors of the films were found to be a mixture of that of relaxor ferroelectrics and normal ferroelectrics. The correlation of the microstructural features (mechanical clamping, small grain size, and epitaxial nature) and the dielectric behaviors was discussed.