Solid-solution thin films of ternary BaTiO3–Bi(Mg1/2Ti1/2)O3–BiFeO3 system epitaxially grown on SrRuO3//SrTiO3 substrates via chemical solution process

Abstract

Lead (Pb)-free perovskite thin films of the ternary BaTiO3–Ba(Mg1/2Ti1/2)O3–BiFeO3 (BT–BMT–BF) solid solution system with preferential crystal orientation were fabricated and the dependence of their polarization behavior on crystal anisotropy was evaluated. The chemical solution deposition (CSD) technique was utilized for the film deposition while controlling the chemical composition. The films fabricated on single-crystal perovskite substrates of (100)SrRuO3//(100)SrTiO3 and (111)SrRuO3//(111)SrTiO3 exhibited preferential (100)pc and (111)pc orientations, respectively, depending on the crystallographic feature on the substrate surface. Excess Bi addition into the precursor solution to compensate for the volatile Bi component enhanced the polarization behavior of the resulting films heat-treated at 750 °C to induce crystallization. The (111)pc-oriented BT–BMT–BF film had a larger remanent polarization (Pr) of approximately 35 µC/cm2 than the (100)pc-oriented film (Pr = approximately 20 µC/cm2).