Effects of La- and V-doping on structural, electrical and multiferroic properties of Bi6Fe2Ti3O18 thin films

Bi6Fe2Ti3O18 (BFTO), (Bi5.25La0.75)Fe2Ti3O18 (BLFTO), Bi6Fe2(Ti2.97V0.03)O18+δ (BFTVO) and (Bi5.25La0.75)Fe2(Ti2.97V0.03)O18+δ (BLFTVO) thin films were prepared on Pt(111)/Ti/SiO2/Si(100) substrates by using a chemical solution deposition method. The effects of La- and V-doping alone and of co-doping on structural, electrical and multiferroic properties of BFTO thin films were investigated. The thin films were crystallized in Aurivillius orthorhombic structure with no secondary phases and no impurities. Among the thin films, a low leakage current density (1.23×10−6 A/cm2 at 100 kV/cm) and a typical hysteresis loop with a large remnant polarization (2Pr) of 36 μC/cm2 and a low coercive field (2Ec) of 146 kV/cm were observed for the BLFTVO thin film. And the thin films showed a weak ferromagnetism at room temperature.