Sputter deposited chromium nitride based ternary compounds for hard coatings

Thin films of chromium based ternary transition metal nitrides Cr1-xMexNy (CrMoN, CrTiN, CrWN and CrNbN) with 0 less than or equal to x less than or equal to 1 were deposited on silicon, glass and high speed steel substrates by reactive magnetron sputtering. The phase, texture and lattice parameter were determined by X-ray diffraction analysis. The surface morphology was examined by scanning tunneling microscopy. The chemical composition was measured by electron probe microanalysis. The cubic phase was the only phase observed for the ternary compounds. Thin films grown at 460 K substrate temperatures exhibit grain sizes of up to 25 nm. The core levels and the valence band were analyzed using X-ray photoelectron spectroscopy. Hardness values, obtained by nanoindentation, vary strongly with the dopant and the doping level. Similarities in changes of the mechanical properties and electronic structure indicate a strong correlation between these properties. (C) 1998 Elsevier Science S.A. All rights reserved.