dark gray; fcc, a=0.4388nm; hardness, 8+ Mohs; electrical resistivity 78μοhm· cm; transition temp 15.2K; can be prepared by heating Nb metal in excess N2 or NH3 to 700°C–1100°C; used in the form of 99.5% pure sputtering target for increasing electrical stability of diodes, transistors, and integrated circuits [KIR81] [CIC73] [CER91]
Dark gray crystals. Transition
temperature 15.2 K. Insoluble in
HCL, HNO3 and H2SO4; but attacked by hot caustic, lime, or
strong alkalis evolving NH3.
Niobium nitride (NbN) thin films were noticed at an early stage because of their critical transition temperatures as low as 16-17K which could find wide applications in superconducting microelectronics. Because of its complicated phase diagram, NbN is difficult to prepare in the pure face-centered cubic, rocksalt structure.
Niobium nitride is used as superconductor. Used in absorbing?anti-reflective coatings. It used to produce arc-welding rods and in steel.