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The first results of the deposition of coatings from accelerated ions of fluorinated fullerene C60(CF3)12 are presented. The coatings are formed at room temperature on Si substrates from a beam of singly charged ions with an energy of 5 keV, as well as from an ion beam that also contains doubly charged ions and a certain amount of ionized fragments of molecules. The properties and structure of coatings obtained from accelerated ions of fluorinated fullerene are compared with the properties and structure of coatings obtained from accelerated fullerene C60 ions under the same conditions. According to X-ray photoelectron spectroscopy (XPS), fluorinated fullerene coatings contain about 4% fluorine. Investigations of the coatings structure and chemical bonds by X-ray photoelectron spectroscopy and Raman scattering show that the presence of fluorine leads to a decrease in the content of sp3-bonds in the coatings and the formation of graphite-like sp2-structures. Coating hardness (H) and Young's modulus (E) compared to C60 ion coatings decrease from 36 to 18 GPa and from 245 to 133 GPa, respectively, while the H/E ratio remains the same (~0.14). Tribological tests have shown for all coatings the friction coefficient is close to 0.1. All coatings are also characterized by a very low wear, less than 10–7 mm3/(N m). For coatings obtained from C60(CF3)12 ions, the contact angle is ~76°–78°. In the absence of fluorine, for the coating obtained from C60 ions, it is ~90°. [ABSTRACT FROM AUTHOR]

From accelerated C60 ions at temperatures of 200 and 300°C hard wear-resistant carbon coatings were deposited. It has been established that the mechanical properties of the coatings are determined by the substrate temperature (Ts) and the energy composition of the beam. The hardness of coatings deposited from ions with an energy of 7 keV exceeds 50 GPa and is practically independent of Ts. The presence of and with an energy of ~14 and 21 keV, respectively, in the beam leads to a result that is not typical for carbon coatings—the hardness increases by more than 1.3 times with an increase in Ts from 200 to 300°C (from 31.6 to 41.6 GPa). In this case, according to Raman spectroscopy data, the size of graphite nanocrystals in the coating increases with temperature up to almost 2 nm. Coatings obtained under conditions of irradiation with and ions are characterized by minimal wear (1.5 × 10–8 mm3/(N m), Ts = 200°C) and minimal friction coefficient (μ = 0.05 for Ts = 300°C). We attribute the unusual dependence of hardness on Ts and the improvement in the tribological properties of coatings to the formation of a composite structure based on a diamond-like matrix and graphite nanocrystals in this Ts range. [ABSTRACT FROM AUTHOR]