PIEZOELECTRIC PROPERTIES OF PZT FILMS PREPARED BY HYDROTHERMAL METHOD
Lead zirconate titanate (PZT) thin films of 5 μm thick were produced by a hydrothermal method on pure titanium substrates. ZrOCl 2-8 H 2 O , Pb ( NO 3)2 and TiO 2 were used as precursors and KOH as a promoter. The hydrothermal synthesis of PZT includes nucleation and crystal growth processes at 120°C or 140°C. The crystallization states were investigated by using scanning electron microscopy and X-Ray diffraction. Piezoelectric properties were evaluated from unimorph cantilever type actuators made of the films. The relationships between the deflection of the actuator due to piezoelectric transverse effect and applied electric field in the direction of thickness of the films showed good linearity. The output voltage from the films under cyclic compressive loading increased with increasing loading frequency, and is saturated at 10 Hz. The PZT films produced by the present methods are satisfactory as a smart material, and are better than the films produced using TiCl 4 as Ti precursor.