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°C. The films annealed at 450–600°C are (110) and (1̱10) biaxis preferential oriented. Below 550°C, the remnant polarization increases with the annealed temperature. The film annealed at 550°C has the largest double remnant polarization of 12.8μC∕cm2. For the film annealed at 600°C, small double remnant polarization of 2Pr=4.6μC∕cm2 was observed for its low breakdown electric field. Besides, the electric property is enhanced with the annealing temperature below 550°C and it is deteriorated for the film annealed at 600°C. Large dielectric constant and low leakage conduction were obtained by the improvement of preparation technology.