Epitaxial V0.6Nb0.4N/NbN superlattices have been deposited on MgO(100) by reactive magnetron sputtering. The V 0.6Nb0.4N alloy was chosen for one layer, rather than VN, in order to reduce the lattice mismatch from 5.7% to 3.5%, allowing growth of superlattices with relatively planar layers. The elastic moduli of NbN and V0.6Nb0.4N are nearly equal, in contrast to previously studied high-hardness nitride superlattices where the layer moduli differed substantially. Vickers microhardness measurements showed no measurable deviation (<4 GPa) from alloy values. The results verify that the difference in layer elastic moduli is the primary parameter determining nitride superlattice hardening.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)