Sputtered barium titanate films for capacitor applications

BaTiO₃ film prepared by RF sputtering was studied for capacitor applications. The films produced have a capacitance storage of 0.85 μF/cm², with a high resistivity of 10¹⁴ Ω-cm and low dissipation factor of 0.005. The dielectric constant of these BaTiO₃ films is approximately 30, which is superior to that of the typical polymer film capacitor and has little dependence on frequency. However, the breakdown strength of BaTiO₃ under the present condition is approximately 30 MV/meter which is about one order magnitude lower than expected. The theoretical breakdown strength of BaTiO₃ is reported to be as high as 200 MV/m. The processing of BaTiO₃ films must be optimized to obtain the potential benefit of the BaTiO₃