Characterization of the density, structure and chemical states of carbon nitride films

Carbon nitride films prepared by rf magnetron sputtering were characterized by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and grazing-incidence X-ray reflectivity. In these films, nitrogen atoms were found to be bound with sp3, sp2 and sp hybridized carbon and about 30% of the CN solid may have C3N4 structure. The nitrogen to carbon ratios (N/C) of the film, sp3 and sp2 CN phases were ∼0.17, 1.05 and 0.26, respectively. The density of the films was about 1.9 g cm−3. The N/C and density of the films only slightly decreased and increased, respectively, with increasing the substrate temperature. The analysis of the annealed samples indicated that these films had a good thermal stability.