Electrical properties of radio frequency magnetron-sputtered (BaSr)TiO3 thin films on indium tin oxide-coated glass substrate

(BaSr)TiO3 thin films were deposited on an indium tin oxide (ITO)-coated glass substrate at the different substrate temperature of 350, 450, and 550 °C by means of rf magnetron sputtering method. The dependency of dielectric constant (ε′) and loss (tan δ) of (BaSr)TiO3 thin films as a function of frequency (0.3–1000 kHz) was studied. It was observed that there was a possibility for the oxidation of the ITO layer to be one of the causes of dielectric anomalies around 100 kHz. Dielectric constant and tan δ became larger with the increase of deposition temperature. As the deposition temperature increases, the leakage current also increases and the breakdown field decreases from 2.5 to 1.97 MV/cm. These variations of electrical properties can be clearly explained by the increase of mobile carrier-oxygen vacancy-in (BaSr)TiO3 thin films.