Epitaxial metallic β-Nb2N films grown by MBE on hexagonal SiC substrates

RF-plasma MBE was used to epitaxially grow 4- to 100-nm-thick metallic beta-Nb2N thin films on hexagonal SiC substrates. When the N/Nb flux ratios are greater than one, the most critical parameter for high-quality beta-Nb2N is the substrate temperature. The X-ray characterization of films grown between 775 and 850 degrees C demonstrates beta-Nb2N phase formation. The (0002) and (21 (3) over bar1) X-ray diffraction measurements of a beta-Nb2N film grown at 850 degrees C reveal a 0.68% lattice mismatch to the 6H-SiC substrate. This suggests that beta-Nb2N can be used for high-quality metal/semiconductor heterostructures that cannot be fabricated at present. (C) 2015 The Japan Society of Applied Physics