The Hall-type ion source operated with nitrogen has been used in two ways in the synthesis of carbon nitride films: by ion beam nitridation of a graphite target and by simultaneous deposition on a collector (silicon wafer and nickel foil) of sputtered carbon atoms and nitrogen atoms from the surrounding nitrogen plasma. We present Rutherford backscattering spectroscopy, x-ray photoelectron spectroscopy and x-ray excited Auger electron spectroscopy results on the carbon and nitrogen atom fraction and chemical bonding state in carbon nitride films. The C 1s XPS peak of a sample deposited on silicon wafer was deconvoluted into three peaks at 284.7, 286.7 and 288.8 eV. The peak at 286.7 eV by analogy with polymethacrylonitrile (C≡N, 286.74 eV) can be identified as C≡N, the peaks at 284.7 and 288.8 eV as C-C and O=C-N, respectively. The N 1s peaks were also deconvoluted into three peaks at approximately 398.3, 400.5 and 402.6 eV. According to the N(E) CKVV spectra the surface samples contain an equal number of sp² and sp³ bonds of carbon atoms.