  The domain structures and dislocations in epitaxial thin films of
La0.7Ca0.3MnO3 grown on SrTiO3 substrates by pulsed laser deposition were
investigated using Bragg-contrast diffraction and high-resolution transmission
electron microscopy. It revealed that the films contained the 1/2[100]o and
1/2[10-1]o types partial threading dislocations, the 90 degree - and 120 degree
- types of twin- domain boundaries, and two types 1/2[010]o, 1/2[111]o, of
antiphase boundaries, which are often observed in bulk materials. In addition,
two types of superdislocations were detected; one consisted of two 1/2[111]o
dislocations and a 1/2[111]o antiphase boundary, and the other was composed of
two 1/2[010]o dislocations and a 1/2[010]o antiphase boundary. These
superdislocations, domain boundaries, and their relationships were extensively
explored.
