Electric properties of BiFeO3 films deposited on LaNiO3 by sol-gel process

Sol-gel process was adopted to prepare BiFeO3 films. Pure phase BiFeO3 films were deposited on LaNiO3 coated Si (111) substrates at various annealing temperatures of 450-600 degrees C. The films annealed at 450-600 degrees C are (110) and (1_10) biaxis preferential oriented. Below 550 degrees C, the remnant polarization increases with the annealed temperature. The film annealed at 550 degrees C has the largest double remnant polarization of 12.8 mu C/cm(2). For the film annealed at 600 degrees C, small double remnant polarization of 2P(r)=4.6 mu C/cm(2) was observed for its low breakdown electric field. Besides, the electric property is enhanced with the annealing temperature below 550 degrees C and it is deteriorated for the film annealed at 600 degrees C. Large dielectric constant and low leakage conduction were obtained by the improvement of preparation technology. (c) 2006 American Institute of Physics.