原子力显微镜结合铁电分析仪研究Nd掺杂Bi4Ti3O12 薄膜的机电性质

Neodymium-doped Bi4Ti3O12 ~BNT! films are evaluated for use as lead-free thin-film piezoelectrics in microelectromechanical systems. Bi4Ti3O12, Bi3.25La0.75Ti3O12 , and Bi3.25Nd0.75Ti3O12 films were fabricated by chemical solution deposition on Pt/TiOx /SiO2 /Si substrates. Nd substitution promoted random orientation with low ~00l! diffraction peaks. The 1- mm-thick Bi3.25Nd0.75Ti3O12 film annealed at 750 °C exhibited a remanent polarization of 26 mC/cm2. Typical butterfly field-induced strain loops were obtained in the BNT film capacitors. The electrically induced strain is 8.431024 under the bipolar driving field of 220 kV/cm. These results show that BNT is a promising candidate for use in lead-free thin-film piezoelectrics.