Superconductivity of<i>B1</i>-MoN films annealed under high pressure

Abstract

B1-phase MoN films, prepared by sputtering, are annealed under a pressure of 6 GPa at temperatures between 600 and 1100 \ifmmode^\circ\else\textdegree\fi{}C for 8 h. The B1-phase MoN is converted mainly to hexagonal-phase and partly to tetragonal-phase ${\mathrm{Mo}}_{2}$N when annealed at temperatures above 750 \ifmmode^\circ\else\textdegree\fi{}C. A residual phase was observed only at an annealing temperature of 600 \ifmmode^\circ\else\textdegree\fi{}C. The ${T}_{\mathrm{co}}$ (the onset of ${T}_{c}$) of 1000 \ifmmode^\circ\else\textdegree\fi{}C-annealed films was 14.9 K; this is the maximum value found in the literature for the Mo-N system.