Improved ferroelectric behavior in (110) oriented BiFeO3 thin films

Abstract

Multiferroic BiFeO3 thin films were grown on LaNiO3 -buffered Pt/TiO2/SiO2/Si substrates by off-axis radio frequency magnetic sputtering, where (110) oriented texture was obtained. The LaNiO3 buffer layer promoted the growth of BiFeO3 film, resulting in a dense texture and columnar growth of BiFeO3 thin films. The BiFeO3 thin film exhibits 2Pr ∼145.8 μC/ cm2 and 2Ec ∼573.5 kV/cm, together with a very low dielectric loss (0.80% at 10 kHz) and an almost fatigue-free behavior at 500 kHz up to 1010 switching cycles. The 2Pr value is comparable to the reported value of the BiFeO3 deposited on the SrTiO3 (110) substrate. While a weak ferromagnetism is demonstrated for the multiferroic thin film at room temperature, the low leakage current and high (110) orientation contribute toward the improved ferroelectric behavior. The BFO thin film with a giant remanent polarization and a fatigue-free behavior promises a candidate material for high-temperature ferroelectric random access memory. © 2010 American Institute of Physics.