Preparation and estimation of Ba0.9Sr0.1TiO3 dielectric films by EPD method with fine powder slurry

摘要

Electrophoretic deposition (EPD) was used to deposit dielectric thin films. A fine Ba_0.9Sr_0.1TiO₃ powder slurry was suspended in acetone and iodine was added to enhance the film quality by increasing the zeta potential. The highest zeta potential was obtained by adding 0.10 g/L of I₂, which allowed a 0.54-μm-thick film to be deposited on a Ni foil in 10 s at 20 V. After annealing the film at 800°C for 30 min in a N₂ atmosphere, the capacitance density of the film was 73.9 nF/cm2 and its loss tangent was 0.021, while the residual leakage current density at 10 V was as low as 0.3 μA/cm2. No frequency dependence was observed in the range 1 kHz to 10 MHz.