Atom probe tomography analysis of different modes of Sb intermixing in GaSb quantum dots and wells

Different modes of intermixing are observed in GaSb/GaAs layers via atom probetomography. The intermixing length scalefor quantum wells of varying thickness is on the order of a monolayer, but three times longer for the wetting layerof a quantum dot structure. The former arises from segregation of Sb and/or surface-induced intermixing via detachment from step edges. The latter is dominated by surface-induced intermixing due to disintegration of the GaSb dots upon capping.