Carbon Nitride (CNX) films have been grown by ion-assisted pulsed-laser deposition (IAPLD). Graphite targets were laser ablated while bombarding the substrate with ions from a broad-beam Kaufman-type ion source. the ion voltage, current density, substrate temperature, and feed gas composition (N2 in ar) have been varied. the resultant films were characterized by Raman, Fourier transform infrared (FTIR), and Rutherford back scattering (RBS) spectroscopy.
Samples with -30% N/C ratio have been fabricated. the corresponding Raman and FTIR spectra indicate that nitrogen is incorporated into the samples by insertion into sp2-bonded structures. a low level of C=N triple bonds is also found. as the ion current and voltage are increased with a pure ar ion beam, Raman peaks associated with nanocrystalline graphite appear in the spectr A. adding low levels of nitrogen to the ion beam first reduces the Raman intensity in the vicinity of the graphite disorder peak without adding detectable amounts of nitrogen to the films (as measured by RBS). at higher nitrogen levels in the ion beam, significant amounts of nitrogen are incorporated into the samples, and the magnitude of the "disorder" peak increases. by increasing the temperature of the substrate during deposition, the broad peak due mainly to sp2-bonded C-N in the FTIR spectra is shifted to lower wavenumber. This could be interpreted as evidence of single-bonded C-N; however, it is more likely that the character of the sp2 bonding is changing.