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Tetrahedral carbon thin films in amorphous modifications (ta-C) are ofinterest for applications due to their excellent hardness, chemical inertness, low friction, and low wear rates. They are obtained by mass-selected and monoenergetic carbon ion beam deposition and by laser ablation ofgraphite '' . The need ofan ion beam with a narrow distributed kinetic energy per C-atom is currently a fundamental obstacle for the use of such thin films in large area and high volume applications. More recently, the deposition of ions abstracted from a radio frequency excited acetylene plasma has yield a hydrogenated form oftetrahedral carbon with properties comparable to ta-C '.An important technological progress can be expected if an ion source can be made available that delivers carbon ions with a narrow-distributed kinetic energy per Catom, that can easily be scaled up, and that can be integrated into existing deposition systems. Due to their high vapour pressure, fullerenes can easily be sublimed and introduced into ion beam and plasma systems and thus have a potential for the deposition oftetrahedral carbon films by relatively simple technological means. The first approach to the use of fullerenes for the deposition oftetrahedral carbon was a cluster ion beam experiment ,in which fullerene ions were accelerated and disintegrated at their impact on a substrate. In another way, fullerenes can be used to generate a plasma ofhigh C2-content due to the effective dissociation ofstrongly heated fullerenes by C2-emission 6 The first use of such a plasma was a chemical vapour deposition experiment, in which fullerenes were dissociated in an argon microwave plasma and nanocrystalline diamond was grown6. The films obtained hereby show superior surface smoothness, low friction and low wear rates .Forthe deposition of amorphous carbon, a Kaufmann-source supplied with fu8 and a radio-frequency (RF) plasma source supplied with fullerenes and argon 10have been applied. Here we report on the ion beam deposition of amorphous carbon by using a fullerene argon plasma without the admixture ofhydrogen. The films are characterized regarding their Raman-emission, their plasmon loss structure and valence band spectra acquired by high-resolution X-Ray photoelectron spectroscopy (XPS), their optical absorption in the visible wavelength regime, and their wetting angles.
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