Growth properties of self-assembled InAs quantum dots on a thin tensile-strained layer

The introduction of a thin tensile-strained GaAs and In/sub 0.32/ Ga/sub 0.68/As right below the QD layer modulates the structural and optical properties of self-assembled InAs QDs embedded in an InAlGaAs matrix. The AFM images indicated that the average size of InAs QDs on GaAs/InAlGaAs is decreased compared to that without the thin GaAs layer, but ones on In/sub 0.32/Ga/sub 0.68/As/InAlGaAs are increased with more isotropic shape.