XPS, XANES and ToF-SIMS Characterization of Reactively Magnetron-sputtered Carbon Nitride Films

✍ Scribed by Lopez, S.; Dunlop, H. M.; Benmalek, M.; Tourillon, G.; Wong, M.-S.; Sproul, W. D.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 444 KB
• Volume: 25
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199709)25:10<827::aid-sia331>3.0.co;2-w

✦ Synopsis

The existence of with hardness characteristics similar or better than diamond was predicted in 1990 by Liu b-C 3 N 4 and Cohen. Many studies have since been devoted to the synthesis of this compound. In the present work, carbon nitride Ðlms were deposited by various reactive magnetron sputtering processes of graphite targets in pure nitrogen and characterized by AES, XPS, x-ray absorption near-edge structure (XANES) and static time-of-Ñight SIMS (ToF-SIMS). Various bonding states (single and double bond) are observed between carbon and nitrogen atoms and between carbon atoms but there is no evidence in the XANES results for either the presence of carbon-nitrogen triple bonds or a pyridine-like ring structure. Surface N/C ratios were estimated to be close to 0.3. Carbon K-edge XANES lineshapes, the C 1s plasmon-loss structure and the calculated density (2.2 g cm-3) indicate that the Ðlms are similar to diamond-like carbon without long-range ordering. The presence of fragments with 1OyAE4 and C x N y the low abundance of and fragments in ToF-SIMS spectra further conÐrm that the carbon atoms do CH x CH x N y not adopt a graphite or pyridine-like cyclic two-dimensional structure and that the Ðlms are not signiÐcantly hydrogenated. A three-phase solid solution model is proposed for the composition of the Ðlms : a "freeÏ carbon phase, an sp3Ècarbon-nitrided phase and an sp2Ècarbon-nitrided phase. The relative proportion of these phases is inÑuenced by the deposition conditions. Enhanced plasma ionization reactive magnetron sputtering leads to higher density and to a higher fraction of the sp3 carbon phase.

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