Twinning rotation and ferroelectric behavior of epitaxial BiFeO3 (001) thin film

Abstract

A twinning rotation structure is revealed by reciprocal space mappings obtained from synchrotron X-ray diffraction for the epitaxial BiFeO3 thin film that was grown on (001) SrTiO3 substrate. The lattice strain is not fully relaxed at a film thickness of 720 nm. The structure is indexed as a monoclinic with lattice parameters a=5.610 (1) Å, b=5.529 (1) Å, c=4.031 (1) Å, and Β=89.34 (1) °. The twinning rotation leads to an enhanced remanent polarization (2 Pr =164 μC/ cm 2, 2 Ec =510 kV/cm) and greatly reduced leakage current density of 1.2× 10-6 A/ cm2 at 100 kV/cm. © 2010 American Institute of Physics.