RF-plasma MBE was used to epitaxially grow 4 – 100-nm-thick metallic
β-Nb2N thin films on hexagonal SiC substrates. When the
N/Nb flux ratios are greater than one, the most critical parameter for
high-quality β-Nb2N is the substrate temperature. The X-ray
diffraction (XRD) of films grown between 775 °C and 850 °C
demonstrates pure β-Nb2N phase formation which was also
confirmed by X-ray photoelectron spectroscopy and transmission electron
microscopy measurements. Using the (0002) and (21
$\bar 3$1) XRD peaks of a β-Nb2N film grown at 850
°C reveals a 0.68% lattice mismatch to the 6H-SiC substrate. This
suggests that β-Nb2N can be used for high-quality
metal/semiconductor heterostructures that cannot be fabricated at present.