Characterization of molecular beam epitaxy grown β-Nb2N films and AlN/β-Nb2N heterojunctions on 6H-SiC substrates

beta-Nb2N films and AlN/beta-Nb2N heterojunctions were grown by molecular beam epitaxy (MBE) on 6H-SiC. The epitaxial nature and beta-Nb2N phase were determined by symmetric and asymmetric high-resolution X-ray diffraction (HRXRD) measurements, and were confirmed by grazing incidence diffraction measurements using synchrotron photons. Measured lattice parameters and the in-plane stress of beta-Nb2N on 6H-SiC were c = 5.0194 angstrom, a = 3.0558 angstrom, and 0.2GPa, respectively. The HRXRD, transmission electron microscopy, and Raman spectroscopy revealing epitaxial growth of AlN/beta-Nb2N heterojunctions have identical orientations with the substrate, abrupt interfaces, and bi-axial stress of 0.88GPa, respectively. The current finding opens up possibilities for the next generation of high-power devices that cannot be fabricated at present. (C) 2016 The Japan Society of Applied Physics