InGaAs/GaAs STRAINED RIDGE QUANTUM WIRES GROWN-BY MBE ON NONPLANAR SUBSTRATE

Abstract

The structures of the strained InGaAs/GaAs ridge quantum wires(QWRs) were proposed and the samples fabricated by MBE growth on patterned substrate. High resolution scanning electron microscope (SEM) studies showed that these ridge structures were formed with (001) top and (113) side faces.The photoluminescence(PL) measurements indicated that the lateral quantum confinement effects of the ridge-QWRs caused the quantum confined energy a 10meV blue-shift, which agreed with the approximate calculations for the strained ridge-QWR structure using Kronig-Penney model. This strainedridge-QWRs consisted of three aspects of lateral confinement effects.Firstly the thickness of ridge quantum wells on the ridge top was larger than that on the side surfaces;Secondly the indium concentrations on the ridge-top region was higher than that on the side region;Thirdly the strain effects led to a larger energy gaps in side (113) plane than that in the (001) ridge top.The above three factors were cooperated to enhance the confinement effects on the lateral motion of carriers in strained ridge QWRs.