Enhancement on effective piezoelectric coefficient d33 of Bi3.15Dy0.85Ti3O12 ferroelectric thin films

Effects of annealing temperature (600-800 °C) on microstructure, ferroelectric and piezoelectric properties of Bi3.15Dy0.85Ti3O12 (BDT) thin films prepared by metal-organic decomposition were studied. The remnant polarization 2Pr and spontaneous polarization 2Ps (16.2 µC/cm2 and 23.3 µC/cm2 under 690 kV/cm), effective piezoelectric coefficient d33 (63 pm/V under the bipolar driving field of 310 kV/cm) of BDT thin film annealed at 700 °C are better than those of others. The higher 2Ps and relatively permittivity εr induced by moderate annealing temperature should be responsible for the enhancement of piezoelectric properties. The improved d33 may make BDT a promising candidate for piezoelectric thin film devices.