Fabrication of self-assembled quantum dots in lattice-matched GaAs/AlGaAs system

Abstract

The formation of self-assembled nanoscale GaAs islands on AlGaAs is demonstrated through the low-temperature molecular beam epitaxy combined with the droplet epitaxy. During the growth of GaAs on the (1 x 1) surface of AlGaAs layer, spotty feature with [111] streaks was observed in the electron diffraction pattern and the resulting nanometer-scale GaAs islands showed {111} facets in surface morphology. Three dimensional growth of GaAs quatum dots is attributed to the limited surface migration of Ga adatoms on the highly As-contained surface at low substrate temperature.