Epitaxial UN and α-U2N3 thin films

Single crystal epitaxial thin films of UN and α-U2N3 have been grown for the first time by reactive DC magnetron sputtering. These films provide ideal samples for fundamental research into the potential accident tolerant fuel, UN, and U2N3, its intermediate oxidation product. Films were characterised using x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS), with XRD analysis showing both thin films to be [001] oriented and composed of a single domain. The specular lattice parameters of the UN and U2N3 films were found to be 4.895 Å and 10.72 Å, respectively, with the UN film having a miscut of 2.6°. XPS showed significant differences in the N-1 s peak between the two films, with area analysis showing both films to be stoichiometric.