Electrical Properties of BaTiO3 Thin Film Grown by the Hydrothermal-Electrochemical Method

Abstract
Crystalline BaTiO3 thin films were prepared directly on Ti substrates in aqueous solutions of Ba(OH)2 at 150 °C by a hydrothermal-electrochemical method and their electrical properties for capacitors were measured. The leakage current-voltage characteristics exhibited rectifications, the degree of which depended on the top electrodes used. Resistivities as high as 1012 Ω· cm were obtained in the voltage range up to 2 V for the 0.40-µ m-thick BaTiO3 thin film and its breakdown voltage was higher than 12 V. The grown films were paraelectric with dielectric constants of 340–350 and dielectric losses of 7–10% at 1 kHz, 0.1 V rms, and 25 °C. The capacitance variation with dc bias voltage from -2.5 to +2.5 V was 9% of the zero-bias value, and that with temperature from -60° to 130 °C was 24% of the room-temperature value.