A twinning rotation structure was 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 was not fully relaxed at a film thickness of 720nm. The structure was indexed as a monoclinic with lattice parameters a = 5.610Å, b = 5.529Å, c = 4.031Å and β = 89.34°. The twinning rotation led to an enhanced remanent polarization (2Pr = 164 μC/cm2, 2Ec = 510 kV/cm) and greatly reduced leakage current density of 1.2 x 10−6A/cm2 at 100kV/cm.

Twinning Rotation and Ferroelectric Behavior of Epitaxial BiFeO3 (001) Thin Film. H.Liu, P.Yang, K.Yao, J.Wang: Applied Physics Letters, 2010, 96[1], 012901