Influence of oxygen gas pressure on phase, microstructure and electrical properties of sodium bismuth titanate thin films grown using pulsed laser deposition

Na0.5Bi0.5TiO3 (NBT) thin films were grown with oxygen gas pressure in the range of 5 Pa and 100 Pa. NBT thin film grown at 30 Pa shows improved properties when compared to films grown at other pressures. This film exhibits single phase and good crystallinity. It has the highest dielectric constant of 754 and lowest dielectric loss of 0.21 at 1 kHz. It has the lowest leakage current of 2 x 10(-6) A/cm(2) measured at 50 kV/cmelectric field. The values of remnant polarization and coercive field, which were measured at room temperature, 10 V and 1 kHz, are 20 mu C/cm(2) and 160 kV/cm respectively. Fatigue study reveals that remnant polarization (+ Pr and -Pr) decreases by 15% after 108 switching cycles. (C) 2015 Elsevier B.V. All rights reserved.