Surfactant effect of Mn on the formation of self-organized InAs nanostructures

Abstract

The effect of Mn as a surfactant on the formation of InAs nanostructures was studied. The shape of the nanostructures changed drastically when a layer of Mn was added on the growth front before InAs growth. When 6 ML 2 1 1 (6 monolayers in (2 1 1) plane) of InAs was grown on GaAs (2 1 1)B with an initial Mn coverage of 0.5 ML, quantum wire-like structures (QWRs) were formed at growth temperatures ranging from 450 to 510°C. With the same initial coverage of Mn, two kinds of nanostructures, quantum dashes (QDHs) and quantum dots (QDs) were formed at 400 or 425°C, whereas only QDs resulted at 380°C. Nanostructures on (1 0 0) and (3 1 1)B surfaces were also investigated and compared.