Growth of Nonpolar AlN and AlGaN on 4H-SiC (1-100) by Molecular Beam Epitaxy

Abstract

AlN and AlGaN have been grown on 4H-SiC (1-100) substrates by rf-plasma molecular beam epitaxy. AlN assumes a metastable 4H structure to match the in-plane stacking arrangement of the substrate. Initial 2D nucleation of 4H-AlN is revealed by reflection high-energy electron diffraction. The epitaxial quality is evidenced by narrow x-ray diffraction ω-scan line widths less than 100 arcsec for symmetric and asymmetric reflections. Structural characterization results for AlGaN/AlN multiple quantum wells are also presented.