Area selective epitaxy of GaAs with AlGaAs native oxide mask by molecular beam epitaxy

Abstract

We have carried out area selective epitaxy of GaAs on GaAs substrates using a native oxide film of AlGaAs as a mask material. By optimizing the AlAs fraction and the thickness of AlGaAs mask layer, well-defined area selective epitaxy has been achieved on (0 0 1) and (1 1 1)B GaAs substrates by migration-enhanced epitaxy. No discernible difference is observed in both the shapes and the facets of the grown structures between the growth using AlGaAs native oxide and SiO 2 masks. It is found that the shape of the grown structures can be easily controlled by As 4 pressure during growth. It has been proved that the AlGaAs native oxide film is useful as a mask material in area selective epitaxy instead of the SiO 2 mask.