Structural and electrical characterizations of Bi(Zn0.5Ti0.5)O3 doped lead zirconate titanate ferroelectric films with enhanced ferroelectric properties

Bi(Zn0.5,Ti0.5)O3 (BZT) doped Pb(Zr0.4,Ti0.6)O3 (PZT) films were fabricated using a chemical solution deposition method and were characterized intensively in the present work. It was discovered that the room temperature remnant polarization and zero-field longitudinal piezoelectric constant of the BZT-doped PZT film were enhanced by 23% and 30%, respectively, as compared with those of the undoped PZT film prepared under the same experiment conditions. In order to explain the improved ferroelectric properties, the phase structures of the BZT–PZT and undoped PZT films were experimentally investigated in a broad temperature range (from 30 to 600 °C) by using the high temperature two-dimensional X-ray diffraction method. It was found that the improvement in ferroelectricity does not correspond to an elevated Curie temperature (TC) or a substantially larger tetragonality (c/a). The difference on the change of TC by doping of Bi-based perovskites in PZT solid solutions between this work and some previous investigations was explained on the basis of Zr/Ti ratio, and the necessity of an in-depth theoretical investigation was addressed.

► Pr and d33 of the fabricated films were enhanced by 23% and 30%, respectively. ► The phase transition process was investigated in a broad temperature range. ► Ferroelectricity improvement does not correspond to a high Curie temperature.