Enhanced leakage and ferroelectric properties of Zn-doped BiFeO3 thin films grown by sol-gel method

Abstract

BiFe1-xZnxO3 (BFZO) (x = 0%, 1%, 2%, 3%) films were deposited on ITO/glass substrates by sol-gel method. We systematically investigated the influence of Zn doping on the crystal microstructure, leakage current, conduction mechanism and ferroelectric behavior of BFZO films. From the XRD patterns, all samples match well with the perovskite structure without impurity phase. Large remnant polarization (2Pr = 129.6 μC/cm2), low coercive field (2Ec = 904 kV/cm) at measured electric field value of 1000 kV/cm were obtained from the BFZO films with x = 2%. Leakage current density curves shows that Zn doping can significantly decrease the leakage current of BFO film in low electric field. In addition, the leakage conduction mechanism transforms from the Ohmic conduction under the low electric field to the F-N tunneling effect under high electric field.