Size, areal density and emission energy control of InAs self assemble quantum dots grown on GaAs by selective area molecular beam epitaxy

Abstract

We report the selective area molecular beam epitaxial (SAMBE) growth of quantum dot (QD) structures. The formation of polycrystalline deposits on dielectric masks is shown to be controlled by the growth rate and growth temperature. Furthermore, we report the size, areal density and energy control of QDs in the region of the dielectric mask. We show that for SAMBE, a reduction in InAs QD size and areal density is obtained close to a polycrstal covered dielectric mask, and that this effect is dependent upon the amount of polycrystalline GaAs coverage of the mask. We attribute this effect to the transport of indium from neighboring epitaxial areas to the polycrystalline GaAs covered mask.