Effects of Transition Metal Ion Doping on Structure and Electrical Properties of Bi0.9Eu0.1FeO3 Thin Films

Pure BiFeO3 (BFO) and europium-transition metal co-doped Bi0.9Eu0.1Fe0.975TM0.025O3-delta (TM = Mn, Co, Ni, Cu, Cr, and Ti) (BEFTM) thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates using a chemical solution deposition method. The effects of co-doping on the crystal structure and the surface morphology of the thin films were examined using X-ray diffraction, Raman spectroscopy and scanning electron microscopy analysis. Systematic investigations on the electrical properties, such as leakage current density and ferroelectric hysteresis loops, have been carried out on the thin films. Reduced leakage current and enhanced remnant polarization (Pr) were observed in the BEFTM thin films. Among the thin films, the BEFCr thin film showed the largest 2Pr value of 89.5 mu C/cm(2). The smallest leakage current density (8.3 x 10(-5) A/cm(2) at 400 kV/cm) was measured from the BEFMn thin film and this value was found to be two orders lower than that of the pure BFO.