Chemical solution deposition derived (001)-oriented epitaxial BiFeO3 thin films with robust ferroelectric properties using stoichiometric precursors (invited)

Phase pure bismuth ferrite (BiFeO3) thin films with (001)-oriented epitaxial structure are realized on lanthanum strontium manganite (La0.67Sr0.33MnO3) buffered (001)-SrTiO3 substrates by chemical solution deposition. The annealing process is optimized such that a stoichiometric precursor can be used to accurately control the Bi: Fe ratio. Ferroelectric, dielectric, and resistive switching behaviours are investigated for 40 nm, 70 nm, and 150 nm BFO thin films. While the thinnest film (40 nm) shows very leaky loops, square and fully saturated polarization hysteresis loops are shown for the thicker films. The highest remanent polarization (2P(r) = 100 mu C/cm(2)) and relative dielectric constant (epsilon(r) = 613) are obtained in the 150 nm BFO thin film. High cycle fatigue tests show that the thick films are resistant to polarization fatigue. Piezoresponse force microscopy results show that the domain structure varies with thickness. Resistive switching and polarization mediated diode effects are also observed. These robust properties suggest that chemical solution deposition derived BiFeO3 thin films can offer a viable low cost alternative. (C) 2014 AIP Publishing LLC.