Study on dielectric, optic and magnetic properties of manganese and nickel co-doped bismuth ferrite thin film

BiFeO3 (BFO), Mn (7.5%)-doped BFO (BFMO), Ni (7.5%)-doped BFO (BFNO), as well as Mn (3.75%) and Ni (3.75%) co-doped BFO (BFMNO) films were deposited on indium tin oxide (ITO)/glass substrates by sol–gel process. X-ray diffraction (XRD) analysis indicated that the BFO and BFNO presented single rhombohedral structure, while BFMO and BFMNO thin films presented tetragonal structure. The current density versus electric field (J–E) characteristics indicated that leakage conduction can be decreased with Mn and/or Ni doped. The films conduction mechanism of BFO and BFNO are space-charge-limited current in the high electric field region, while for BFMO and BFMNO is Ohmic’s conduction in all electric field region. The optical band gap of the BFO, BFMO, BFNO and BFMNO thin films are 2.18, 2.22, 2.3 and 2.32 eV, respectively. The inhomogeneous spin-modulated magnetic structure of BiFeO3 was modified by Mn and/or Ni substitution.