Growth and Characterization of GaN/InxGa1−xN/InyAl1−yN Quantum Wells by Plasma-Assisted Molecular Beam Epitaxy

Abstract

The nearly lattice-matched InxGa1−xN/InyAl1−yN epi-layers were grown on a GaN template by plasma-assisted molecular beam epitaxy with a metal modulation technique. The band-gap energy of InxGa1−xN QW in photoluminescence measurement was estimated to be 2.89 eV and the indium concentration (x) was 14.8%. In X-ray photoelectric spectroscopy, we obtained an indium concentration (y) in the InyAl1−yN barrier of 25.9% and the band-offset was estimated to be 4.31 eV. From the atomic layer measurements from high-resolution transmission electron microscopy, the lattice misfit between the InxGa1−xN QW and InyAl1−yN barrier was 0.71%. The lattice-matched InxGa1−xN/InyAl1−yN QWs can therefore be evaluated from the band profiles of III-nitrides for engineering of full-visible-light emitting diode in optoelectronic application.