Self-assembled InAs quantum dots on GaSb/GaAs(0 0 1) layers by molecular beam epitaxy

Abstract

Self-assembled InAs quantum dots (QDs) were grown on one-monolayer-thick GaSb/GaAs(0 0 1) layer by molecular beam epitaxy using Stranski–Krastanov mode. High dot density of about 1 × 10 11 cm - 2 was demonstrated on the GaSb/GaAs buffer layer. In spite of high dot density, coalescence of neighboring dots was effectively suppressed on the GaSb surface. InAs coverage dependence of the dot structure was studied by using atomic force microscopy and reflection high-energy electron-beam diffraction. For large InAs coverage, the {1 1 0} facet appeared on the side wall of the large dots, and, a narrow PL linewidth of 33 meV could be obtained from highly dense InAs QDs.