Carbon nitride layers were deposited on unheated Si(100) substrates by CO2 IR laser ablation of graphite in a remote nitrogen plasma atmosphere. The diagnostic techniques Fourier-transform infrared (FTIR) and Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and resistivity measurements were used to characterize the layers deposited. These characteristics were studied as a function of nitrogen pressure. The deposits have a granular structure with a fairly rough surface, as observed by SEM and AFM. Raman spectroscopy shows a change in the size of sp2 cluster domains and gives an idea of the disorder of the deposit network. These cluster-size changes, in accordance with the AFM and SEM analyses, induce some modification of the deposit porosity, which could explain the increase in film resistivity. The XRD measurements indicate that the deposit could contain some α-C3N4 crystals that are dispersed in an amorphous graphite like phase.