Growth of 0.1(Bi,Na)TiO₃–0.9BaTiO₃ epitaxial films by pulsed laser deposition and their electric properties

Abstract

0.1(Bi,Na)TiO₃–0.9BaTiO₃ thin films were deposited by pulsed laser deposition as a candidate of lead-free thin films with a positive temperature coefficient of resistance for micro-thermistor applications in microelectro mechanical system devices. (001)-oriented epitaxial tetragonal films with a unity (Bi + Na + Ba)/Ti ratio were grown at 675 °C under a total pressure of 50 mTorr. The obtained films showed improved insulating properties and clear ferroelectricity. The Curie temperature was estimated to be 200 °C by the high-temperature X-ray diffraction measurement, which was almost the same as the reported value for the ceramic.