PROPERTIES OF CARBON NITRIDE FILMS DEPOSITED BY MAGNETRON SPUTTERING

Carbon nitride films have been deposited by r.f. and d.c. planar balan ced magnetron sputtering under various conditions. The films were anal ysed by Rutherford back-scattering (RBS), electron energy loss spectro scopy (EELS), and Fourier transform infrared (FTIR) spectroscopy. The deposition rates of the films synthesised by r.f. magnetron sputtering increased with nitrogen content in the sputtering gas. The nitrogen c ontent of the films also increased as the nitrogen content in the sput tering gas was increased to 50 vol.%, and then remained constant. Abso rption bands at 1250, 1550 and 2200 cm(-1) were detected in FTIR spect ra, corresponding to Raman-reactive disordered sp(2) carbon, graphite- like sp(2) carbon, and nitrile or isocyanate groups, respectively. Add itionally, broad absorption around 1000-1200 cm(-1) which may be assoc iated with sp(3) hybridised carbon, was observed in films deposited wi th low nitrogen content in the sputtering gas. Sputtering gas total pr essure and sputtering power were also varied. The results were interpr eted in terms of the collision frequency of the sputtered species with reactive gases in the system. The films deposited with > 70% nitrogen in the sputtering gas showed higher friction coefficients and lower w ear resistance in sliding friction tests than films grown with lower g as nitrogen content, suggesting that these properties of the films wer e associated with their structure. (C) 1998 Elsevier Science S.A. All rights reserved.