Misfit dislocations in layers which had been grown onto Si substrates by means of metalorganic chemical vapor deposition were characterized by using high-resolution transmission electron microscopy. The lattice mismatch of GaAs on Si was completely relaxed by misfit dislocations. The Burgers vector of the misfit dislocation was greatly affected by the growth mode in the initial stages of growth. It was found that Lomer misfit dislocations predominated when the epitaxial layer grew 3-dimensionally in the initial stages (GaAs on Si, AlGaAs on Si), and that 60° dislocations predominated when the epitaxial layer grew 2-dimensionally in the initial stages (GaP on Si). A mechanism was proposed for Lomer misfit dislocation generation in the case of 3-dimensional growth.

T.Soga, T.Jimbo, M.Umeno: Journal of Crystal Growth, 1994, 145[1-4], 358-62