Reduced leakage current, enhanced ferroelectric and dielectric properties in (Ce,Fe)-codoped Na0.5Bi0.5TiO3 film

Na0.5Bi0.5TiO3 (NBT), Ce-doped NBT (NBTCe), Fe-doped NBT (NBTFe), and (Ce,Fe)-codoped NBT (NBTCeFe) thin films were fabricated on LaNiO3(100)/Si substrates by metal organic decomposition. The leakage current density of NBTCeFe at 500 kV/cm is reduced by approximately two orders of magnitude by reducing the density of oxygen vacancies and forming the defect complexes, compared with NBT film. Enhanced ferroelectricity is achieved in NBTCeFe with a large remanent polarization of 24 mu C/cm(2) due to the reduced leakage current, extra A-site vacancies, and lattice distortion. The NBTCeFe also exhibits a dielectric constant of 585 and dielectric loss of 0.05 at 10 kHz. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3676663]