Interfaces between Si and epitaxial GaAs thin films, grown using metal-organic chemical vapor deposition, were studied using atomic-resolution Z-contrast imaging. The latter provided chemical composition information and permitted the direct interpretation of micrographs, without simulation. Three different types of dislocation were identified. As expected, a dangling bond was found in the atomic structure of the 60° dislocation. One of the observed 90° dislocations had a reconstructed atomic core structure (with no dangling bonds). The core structure of the other 90° dislocation exhibited a dangling bond.

Z-Contrast Imaging of Dislocation Cores at the GaAs/Si Interface. S.Lopatin, S.J.Pennycook, J.Narayan, G.Duscher: Applied Physics Letters, 2002, 81[15], 2728-30