The reactive pulsed laser deposition technique was used to deposit carbon nitride .CN x / coatings on a silicon substrate. In this process, an infrared transversely excited atmospheric pressure CO 2 laser ablation of a graphite target in a remote nitrogen plasma afterglow was used to provide simultaneously both carbonand nitrogen-containing species. Evidence of different CN bonding configurations has been observed in the deposited coatings. For nitrogen pressures (P N 2 ) of ≥700 Pa there is an increase in the contribution of sp 2 carbon atoms that is associated with graphitization of the CN x coatings. For P N 2 increasing from zero to 100 Pa, the comparison between XPS core-level and valence band spectra of the CN x coatings shows good correlation between the p-derived states (C 2p electrons) of C-C p bonds in the valence band and the sp 2 carbon atom concentration deduced from the C 1s spectra.The progressive positive contribution of nitrogen lone pair electrons to the valence band is consistent with the increase of the N-C sp 3 contribution with P N 2 . The decrease in the sp 2 carbon atom contribution is associated with the increase of the nitrogen concentration in the coatings.

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