SURFACTANT-MEDIATED MOLECULAR-BEAM EPITAXY OF HIGH-QUALITY (111)B-GAAS

We present a novel approach to the molecular beam epitaxy of [111]-oriented GaAs. Surface-segregating In employed as an isoelectronic surfactant allows us to achieve mirror-like (111) GaAs surfaces within a wide range of growth conditions. Scanning electron and atomic force microscopy confirm the excellent morphology of the resulting samples. High-resolution X-ray diffraction shows the incorporation of In into the films to be negligible. Finally, we demonstrate a 10 angstrom-In0.2Ga0.8As/300 angstrom-GaAs superlattice based on surfactant-grown GaAs with a photoluminescence linewidth as narrow as 4.2 meV.