Site-controlled self-assembled InAs quantum dots grown on GaAs substrates

Abstract

Atomically-flat surfaces are obtained after thin GaAsSb buffer layer growth on GaAssubstrates with regular-distributed nano-holes formed after oxide desorption of the localatomic-force-microscopy anode oxidation. Different from the samples with GaAsSbbuffer layers, increasing surface root-mean-square roughness is observed for theGaAs-buffered samples with increasing GaAs buffer layer thickness. The phenomenon isattributed to the enhanced adatom migration resulting from the incorporation ofSb atoms. By using the substrates with nano-holes after buffer layer growth,site-controlled self-assembled InAs quantum dots (QDs) are observed with thedeposition of a below-critical-thickness InAs coverage of 1.3 monolayer (ML).