Abstract: | Carbon nitride films were deposited by direct current plasma assisted pulsed laser ablation of a graphite target under a nitrogen atmosphere at room temperature. The surface morphology, composition and bonding structure of the deposited films were characterized by atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, Raman, and X-ray photoelectron spectroscopy (XPS). The effect of laser fluences in the range 0.5–3 J/cm2 on the surface morphology, composition and bonding structure of the carbon nitride films were systematically studied. As laser fluence is increased, AFM results show a great decrease in the surface roughness of carbon nitride films. FTIR and XPS results indicate an increase in the N/C ratio and the content of N atoms bonded to sp3 C, as well as a decrease in the content of H atoms and the content of N atoms boned to sp2 C in the deposited films, and Raman spectra indicate an increase in the content of disordered sp2 C atoms and the sp2 cluster size. The increase in the film density and the decrease in the particle fraction contribute to the decrease of surface roughness with increasing laser fluence. |