Preparation and electrical properties of BST thick film deposited by electrophoretic deposition method

Ba_0.6Sr_0.4TiO₃ (BST40) thick film with thickness of 33 μm was prepared by electrophoretic deposition method on Pt/Ti/SiO₂/Si substrate using the BST40 nano powders as precursor. A high pressure treatment process was introduced in order to increase the density and decrease the sintering temperature of the film. The composition and surface morphology of the BST40 thick film were characterized. The ε-V curve of the BST40 thick film was measured. The leakage current density was tested and hysteresis loops of the thick film were measured at different temperatures. The results show that a dense and no crack surface are formed after sintering at 950°C. A tunability of 59.2% is calculated according to the ε-V curve. The leakage current is less than 100 μA/cm 2 when the applied voltage shifts from -25 V to 25 V. The remnant polarization is 1.06 μC/cm2 at the temperature of 0°C and the frequency of 1 kHz.