Preparation and Characterization of BaTiO₃ Thin Films Using Reactive Sputtering Method with Metal Target

Abstract

BaTiO₃ thin films were grown on (100)MgO single crystal substrates by reactive sputtering using Ba and Ti metal targets, and optimization of deposition conditions for fabricating high-quality BaTiO₃ thin films were investigated. Composition of BaTiO₃ thin films was controlled by the number of Ba metal pieces. As a result, the total pressure of 20 Pa and Ba/Ti target area ratio of 0.17 was optimized for fabricating stoichiometric BaTiO₃ thin film. Under this condition, BaTiO₃ thin film can be crystallized at 460°C. From X-ray diffraction analysis, we confirmed that the BaTiO₃ thin film, which deposited under optimum conditions of deposition temperature of 460°C, total pressure of 20 Pa, and Ba/Ti target area ratio of 0.17, was epitaxially grown and had (100)/(001) single orientation. Lattice constants of the a- and c-axis were estimated to be 0.4063 and 0.4098 nm, respectively. Therefore, we concluded that it can be successful in fabricating high-quality and low damage BaTiO₃ thin film deposited by reactive sputtering using a metal target at a low temperature.

Keywords:

• Barium titanate
• metal target
• reactive sputtering
• thin film
• MgO substrate

Acknowledgments

This work was partly supported by a Grant-in-Aid for Scientific Research (C) (No. 22560679) from the Ministry of Education, Culture, Sports, Science and Technology, Japan.