Transmission electron microscopy study on ferroelectric domain structure in SrBi2Ta2O9 ceramics

A transmission electron microscopy investigation has been conducted on the domain structure in SrBi2Ta2O9 ceramics. From the 90 degrees rotation relat ionship of the electron diffraction pattern of the [001] zone axis, a 90 de grees domain wall can be confirmed. It is due to the failure of Friedel's l aw that the contrast of a 180 degrees domain wall can be identified. The an tiphase boundary can be seen clearly in the dark-field image, which is take n by the (300) superlattice reflection. The 90 degrees domain wall, as well as antiphase the boundary (APB), has an irregular configuration. The APB c ombined with the 90 degrees domain wall is also identified. (C) 2000 Americ an Institute of Physics. [S0003-6951(00)02101-X].