Carbon (C), carbon nitride (CNx), C-nickel and CNx-nickel films were deposited by direct current magnetron sputtering onto oxidized (100) Si substrates, at 25, 200, and 500 degrees C growth temperatures. Raman spectroscopy was used to examine the bonding structure of C and CNx, and to investigate the effect of the Ni dispersed phase on the atomic structure of the C or CNx matrix of composite films. The atomic structure of the matrix is different for the C-Ni and for the CNx-Ni films. In the C and C-Ni films graphene-like sp(2)-ordering, in the CNx and CNx-Ni films fullerene-like sp(2)-ordering was found. For both types of composite films, the presence of the dispersed phase enhances the sp(2)-ordering of the matrix. (C) 2009 Elsevier B.V. All rights reserved.