Dielectric properties of BaTiO₃–Bi(Mg_1/2Ti_1/2)O₃ films with preferential crystal orientation

Abstract

Thin films of the BaTiO₃–Bi(Mg_1/2Ti_1/2)O₃ (BT–BMT) solid-solution system with preferential crystal orientation of (100) and (111) plane were fabricated on (100)SrRuO₃//(100)SrTiO₃ and (111)SrRuO₃//(111)SrTiO₃ substrates by CSD technique. Enhanced dielectric permittivity (ε_r) of approximately 800 was confirmed for the (111)-oriented BT–BMT film at room temperature, which is significantly larger than those of (100)- or randomly-oriented films. The BT–BMT films exhibited relatively stable temperature coefficient of capacitance (TCC) independent of their crystal orientation, that allows enhanced ε_r up to 400°C without drastic change of the capacitance. These properties can be favorable for the application of dielectric capacitors in high-temperature electronics.