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Elseiver. Surface and Coatings Technology xx (2007) xxx–xxx Carbonaceous thin films can be used in microelectronics, superconductors, solar batteries, logic and memory devices, and to increase processing tool wear resistance, and as magnetic nanocomposite materials for information storage. This paper presents a study of carbonaceous thin films deposited on silicon substrates using ablation plasma generated by pulsed power ion beams (H+—60%, C+—40%, E=500 keV, τ=100 ns, density=8 J/cm2) on graphitic targets. The concentrations of sp3-bonded crystalline diamond, and amorphous and crystalline phases of carbon were determined by X-ray diffraction analysis (XRD). It was observed that the concentration of the crystalline diamond phase in films deposited under various conditions did not exceed 5%. A substantial concentration (30–95%) of the carbon crystalline phase is in the form of C60 and C70 fullerenes. It is shown that the concentration of fullerenes and the ratio between the relative amounts of C60 and C70 greatly depends on the graphitic target density, carbon film deposition conditions and above all on the distance from the graphitic target to the silicon substrate. This distance determines the film deposition rate and the degree of cooling of the plasma generated on the substrate, which can cause changes in film crystallization conditions.
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Surface & Coatings Technology xx (2007) xxx – xxx www.elsevier.com/locate/surfcoat
Carbon film deposition by powerful ion beams A.I. Ryabchikov a , A.V. Petrov a , N.M. Polkovnikova a , V.K. Struts a,⁎, Yu.P. Usov a , V.P Arfyev b a
Nuclear Physics Institute, Lenin ave., 2a, Tomsk, 634050, Russia Tomsk Polytechnic University, Lenin ave., 30, 645050, Russia
b
Abstract Carbonaceous thin films can be used in microelectronics, superconductors, solar batteries, logic and memory devices, and to increase processing tool wear resistance, and as magnetic nanocomposite materials for information storage. This paper presents a study of carbonaceous thin films deposited on silicon substrates using ablation plasma generated by pulsed power ion beams (H+—60%, C+—40%, E = 500 keV, τ = 100 ns, density = 8 J/cm2) on graphitic targets. The concentrations of sp3-bonded crystalline diamond, and amorphous and crystalline phases of carbon were determined by X-ray diffraction analysis (XRD). It was observed that the concentration of the crystalline diamond phase in films deposited under various conditions did not exceed 5%. A substantial concentration (30–95%) of the carbon crystalline phase is in the form of C60 and C70 fullerenes. It is shown that the concentration of fullerenes and the ratio between the relative amounts of C60 and C70 greatly depends on the graphitic target density, carbon film deposition conditions and above all on the distance from the graphitic target to the silicon substrate. This distance determines the film deposition rate and the degree of cooling of the plasma generated on the substrate, which can cause changes in film crystallization conditions. © 2007 Elsevier B.V. All rights reserved. Keywords: Ion beam; Carbonaceous film; Fullerene; Film deposition
1. Introduction Amorphous carbon films possess good tribological properties such as high hardness and low friction coefficient, which result in significant increase in wear resistance of articles with such coatings [1,2]. Diamond-like carbon films with sp3 bonding possess high mechanical strength, low friction coefficient, high corrosion resistance, and good insulation and optical properties. These properties enable them to be used as protective films, vibration plates for sound sources, and for domestic water pumps, etc. [3]. Carbon allotropic forms – fullerenes C60 and C70 and nanotubes – possess wider