Carbon nitride films produced by high-energy shock plasma deposition

Abstract

High-energy shock plasma deposition techniques are used to produce carbon-nitride films containing both crystalline and amorphous components. The structures are examined by high-resolution transmission electron microscopy, parallel-electron-energy loss spectroscopy, and electron diffraction. The crystalline phase appears to be face-centered cubic with a unit cell parameter approx. a = 0.63 nm, and it may be stabilized by calcium and oxygen at about 1–2 at. % levels. 85 at. % of the carbon atoms appear to have trigonal bonding for the crystalline phase, the remaining 15 at.% having tetrahedral bonding. The amorphous carbon-nitride film component varies from essentially nanocrystalline graphite, containing virtually no nitrogen, to amorphous carbon-nitride containing up to 10 at. % N, where the fraction of sp3 bonds ranges up to approx. 85 at. %. There is PEELS evidence that the nitrogen atoms have sp2 trigonal bonds in both the amorphous and crystalline phases.