Self-assembled quantum dots of InSb grown on InP by atomic layer molecular beam epitaxy: Morphology and strain relaxation

Self-organized InSb dots grown by atomic layer molecular beam epitaxy on InP substrates have been characterized by atomic force and transmission electron microscopy. Measurement of high-energy electron diffraction during the growth indicates a Stransky-Krastanov growth mode beyond the onset of 1.4 InSb monolayer (ML) deposition. The dots obtained after a total deposition of 5 and 7 hit of InSb present a truncated pyramidal morphology with rectangular base oriented along the [110] directions, elongated forwards the [110] direction with {111}B lateral facets, with {113}/{114}/{111}A lateral facets in [1 (1) over bar 0] views, and (001) flat top surfaces. The mismatch between the dot and the substrate has been accommodated by a network of 90 degrees misfit dislocation at the interface. A corrugation of the InP substrate surrounding the dot has been also observed. (C) 1996 American Institute of Physics.