Multiferroic properties of Bi(Fe0.5Sc0.5)O 3-Pb TiO3 thin films

Abstract

Bi(Fe0.5Sc0.5)O3-PbTiO3 (BSF-PT) thin films were grown on LaNiO3/Si and Pt/TiO 2/SiO2/Si substrates by pulsed laser deposition. The structure-microstructure-property relations of the films were the investigated using x-ray diffraction and scanning electron microscopy in conjunction with ferroelectric and magnetic measurements. BSF-PT films grown on Pt/TiO 2/SiO2/Si substrates show a remnant polarization, P r>40 μC cm-2, and a coercive field, E c=1000 kV cm-1. In contrast, films grown under the same deposition conditions on LaNiO3/Si substrates have Pr=20 μC cm-2 and Ec=200 kV cm-2. Moreover, the leakage current density of the film on Pt is reduced by two orders of magnitude from 2×10-4 to 1×10-6 A cm-2. A commensurate improvement in ferromagnetic properties is also observed. Overall, the substitution of Sc for Fe improves the ferroelectric switching behavior and properties and enhances the magnetic moment with respect to BiFeO 3-PbTiO3. © 2010 The Royal Swedish Academy of Sciences.