Composition and physical properties of thin a-C:N and a-C:N:H films deposited by ion beam techniques

Thin a-C, a-C:N, a-C:H and a-C:N:H films were deposited onto silicon, glass and graphite substrates using ion beam techniques. Rutherford backscattering spectroscopy and elastic recoil detection analysis were performed in order to determine their atomic composition. The hardness of these films were measured using a Vickers hardness diamond indenter. The as-deposited a-C:H and a-C:N:H films were characterized using optical absorption spectroscopy, while the a-C and a-C:N films were studied by Raman spectroscopy. A shift of the absorption edge toward the lower energy region and a lower gap of a-C:N:H films was observed. The Raman spectra of a-C:N films show an increase in the I(D)/I(G) ratio, as compared to those of non-nitrogenated diamond-like carbon films. A possible structure is suggested. (Author)