Influences of surface texture and Bi/Fe ratio on electric properties of BiFeO3 thin films prepared by chemical solution deposition

We have investigated the influences of surface texture and Bi/Fe ratio on the electric properly of BiFeO3 thin films prepared by chemical solution deposition. All the BiFeO3 films have;l rosette structure, which consists of circular regions with BiFeO3 crystals and outer regions with amorphous phase. Circular regions tend to increase with an increase in Bi/Fe ratio. Leakage current increases with an increase in the area of circular regions and in surface roughness as well as with an increase in Bi/Fe ratio. On the other hand. remanent polarization increases with an increase in the area of circular regions as well as with an increase in Bi/Fe ratio, but decreases in a BiFeO3 film prepared using a 20 mol % Bi-excess solution owing to the mixed phase. Consequently, a 10 mol % Bi-excess solution gives the best ferroelectric property for a BiFeO3 thin film with more circular regions and its remanent polarization is 85 mu C/cm(2).