Growth of InGaAs quantum dots on the AlGaAs(311)B surface

We have investigated the self-organization mechanism of InGaAs quantum dots (QDs) on GaAs(311)B substrates by changing the underlying materials beneat h the QD layer. It was found that the QD growth on the (311)B surface is st rongly affected by the underlying layer. The size uniformity and structure ordering of QDs were degraded if the QDs were grown on an AlGaAs layer, How ever. these properties of QDs were recovered by introducing a 40-nm-thick G aAs spacer layer on AlGaAs. The dependence of the QD properties on the spac er layer thickness suggested that there exists a long-range interaction bet ween the InGaAs QDs and the underlying layer in the case of QD growth on th e (311)B surface. This long-range interaction is considered to arise from t he steep change in strain distribution at the interface of GaAs and AlGaAs and/or intermixing of the InGaAs layer with the underlying layer.