Self-assembled InSb quantum dots in InAs and GaSb matrices assessed by means of TEM, AFM and PL

Abstract

Transmission electron microscopy (TEM), atomic force microscopy (AFM) and photoluminescence (PL) with and without additional magnetic fields (magneto-PL) were employed to study metal organic vapour phase epitaxy (MOVPE) grown, self-assembled InSb rich quantum dots (QDs) embedded in InAs and GaSb matrices. Depending on the growth conditions, coherently strained, partly relaxed, and completely relaxed InSb rich agglomerates were observed by means of TEM; AFM delivered more reliable QD number densities and accurate heights of InSb islands on GaSb. For the case of InSb embedded in GaSb, PL showed QD emission at 1.69 mum and wetting layer (WL) emission at 1.61 mum