Effect of oxygen pressure on the electrical properties of Bi5Nb3O15 films grown by RF magnetron sputtering

Abstract

Bi5Nb3O15 (B5N3) films grown under a low oxygen partial pressure (OP) of 1.7 mtorr showed a high leakage current density of 0.1 A/cm(2) at 1.0 MV/cm. However, the leakage current density decreased with increasing OP to a minimum of 5.8 x 10(-9) A/cm(2) for the film grown under 5.1 mtorr due to the decreased number of oxygen vacancies. This film also showed an improved breakdown field of 2.2 MV/cm and a large capacitance density of 24.9 fF/mu m(2). The electrical properties of the film, however, deteriorated with a further increase in OP, which is probably due to the formation of oxygen interstitial ions. Therefore, superior electrical properties for the B5N3 film can be obtained by careful control of OP.