Influences Of Surface Texture And Bi/fe Ratio On Electric Properties Of Bifeo_3 Thin Films Prepared By Chemical Solution Deposition

摘要

We have investigated the influences of surface texture and Bi/Fe ratio on the electric property of BiFeO_3 thin films prepared by chemical solution deposition. All the BiFeO_3 films have a rosette structure, which consists of circular regions with BiFeO_3 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 BiFeO_3 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 BiFeO_3 thin film with more circular regions and its remanent polarization is 85 μC/cm~2.