Dependence of the electrical properties on grain-boundary plane orientation was

examined by a combination of high-resolution transmission electron microscopy,

impedance spectroscopy, and electron energy-loss spectrometry using two kinds of

SrTiO3 Σ5 ([100]/36.8°) bicrystalline grain boundaries: symmetric (310)

(18.4°/18.4°) and asymmetric (8.4°/28.4°). While the symmetric grain boundary

was observed to be straight with the symmetric (310)//(310) plane orientation, the

asymmetric grain boundary was faceted into symmetric (310)//(310) and

(210)//(210), and asymmetric (100)//(430). Grain-boundary impedance was

observed only in the asymmetric grain boundary, and the electron energy-loss

spectrometry quantification indicates that the asymmetric (100)//(430) facets were

more oxygen-deficient than the symmetric ones. The results suggested that the

asymmetric (100)//(430) facets were the most resistive among the three different

facets.

Grain-Boundary Plane Orientation Dependence of Electrical Barriers at Σ5

Boundaries in SrTiO3. S.B.Lee, J.H.Lee, Y.H.Cho, D.Y.Kim, W.Sigle, F.Phillipp,

P.A.Van Aken: Acta Materialia, 2008, 56[18], 4993-7