Improvement of leakage and ferroelectric properties of Mn-doped BiFeO3 thin films

A series of Mn-doped BiFeO3 (BFO) films were successfully deposited on the ITO/glass substrates by sol-gel method combining layer by layer annealing process. The effects of Mn content on the film texture, leakage current, conduction mechanism and ferroelectric behavior of the deposited BFO films were systematically investigated. Compared to undoped BFO thin films, all the Mn-doped films showed refined grains, defectless microstructure and improved electric properties. The conduction mechanism changed from space charge limited conduction (SCLC) to Ohmic conduction gradually as Mn content increased. Meanwhile, the Mn-doped BFO films showed remarkable asymmetrical coercive field, which was induced by the high content of defect complexes of (V-O2)(center dot center dot)-(A(Fe3+)(2+))'.