Enhanced ferroelectric, dielectric and leakage properties in Ce and Ti co-doping BiFeO3 thin films

Abstract

Pure BiFeO3 (BFO), Ce and Ti individual doping and co-doping BiFeO3 thin films were fabricated via sol–gel process on Pt/Ti/SiO2/Si substrates. The microstructure, surface morphology, ferroelectric and dielectric properties of BFO and doped thin films were investigated in detail. X-ray diffraction reveal that all thin films are confirmed the formation of the distorted rhombohedral perovskite structure. No impure phase is identified in all the films. The Ce and Ti co-doping BiFeO3 (BCFTO) thin films exhibited the enhanced ferroelectricity with a large remnant polarization (2Pr) of 130 μC/cm2, and low leakage current density of 9.10 × 10−6 A/cm2 which is more than two orders of magnitude lower than that of pure BFO films at 100 kV/cm. The dielectric constant (364 at 1 kHz) of the BCFTO thin films is much larger than that of pure BFO thin films. These results suggest that the introductions of Ce and Ti provides an effective route for improving the ferroelectric, dielectric and leakage properties of BFO thin films.