Fabrication of V-substituted (Bi, M)₄Ti₃O₁₂ [M = lanthanoids] thin films by chemical solution deposition method

Bismuth titanate (Bi₄Ti₃O₁₂; BIT)-based ferroelectric materials are proposed from the view of the "Site-engineering", where the Bi-site ions are substituted by lanthanoid ions (La³⁺ and Nd³⁺) and Ti-site ions by other ions with higher charge valence (V⁵⁺). In the present study, influences of vanadium (V) - substitution for (Bi, M)₄Ti₃O₁₂ thin films [M = lanthanoid] on the ferroelectric properties are evaluated. V-substituted (Bi, M)₄Ti₃O₁₂ films have been fabricated using a chemical solution deposition (CSD) technique on the (111)Pt/Ti/SiO₂/(100)Si substrate. Remnant polarization of (Bi, La)₄Ti₃O₁₂ and (Bi, Nd)₄Ti₃O₁₂ films has been improve by the V-substitution independent of the coercive field. The processing temperature of BLT and BNT films could also be lowered by the V-substitution.