Application-relevant characterization of magnetron-sputtered carbon nitride films

Carbon nitride (CNx) films were deposited onto Si substrates by radio frequ ency magnetron sputtering at nitrogen pressures up to 0.3 Pa (the resulting nitrogen concentration ranged from 32 to 41%). Their optical properties, s tructure and bonding were characterized by spectroscopic ellipsometry, X-ra y diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. The films exhibit a behavior typical for disordered systems, and no known C3N4 structure was identified. A pronounce d effect of the nitrogen partial pressure is found for the low pressure reg ion. The presence of various types of C-N bond, as well as of hydrogen and oxygen, is revealed. The complementarity of information inferred from Raman and IR spectra is discussed. (C) 1999 Elsevier Science S.A. All rights res erved.