Characterizations of CN x thin films made by ionized physical vapor deposition F. Te ´tard * , P. Djemia, M.P. Besland, P.Y. Tessier, B. Angleraud Laboratoire PMTM UPR CNRS 9001, Universite ´ Paris Nord-Institut Galile ´e, 99 Av. J.B. Cle ´ment, Villetaneuse Cedex 93430, France LPCM, Institut des Mate ´riaux J. Rouxel UMR 6502-CNRS, 2 rue de la Houssinie `re, Nantes 44322, France Available online 11 January 2005 Abstract Thin films of CN x deposited by physical vapor deposition (PVD) with different contents of nitrogen have been studied. An RF-powered antenna was added to a classical magnetron sputtering system. The addition of an antenna plays an important role in mechanical and physicochemical properties. The films have been characterized using XPS, AFM, Brillouin light scattering, grazing angle FTIR, and wettability test. The results show in particular that the Rayleigh wave velocity determined by BLS increased when deposit is assisted by the antenna. Refractive index and surface tension are also enhanced with the use of an antenna. Moreover, high deposition rates are obtain with antenna without modification of N/C ratio. D 2004 Elsevier B.V. All rights reserved. Keywords: Cnx; Ionized PVD; Antenna; FTIR; Brillouin light scattering; Wettability 1. Introduction This work deals with the deposition of carbon-based materials made by magnetron sputtering: carbon (C) and carbon nitride (CN x ) films. Using a modified magnetron sputtering deposition system, an RF-powered coil (or antenna) has been added to a standard magnetron sputtering apparatus. As previous studies concerning film deposition [1,2] have demonstrated very interesting results (improve- ment of the plasma species excitation, high floating substrate potential generated, selective area deposition, and increase of the deposition rate with no modification of the chemical composition), the influence of the coil onto the mechanical and physicochemical properties has been investigated. 2. Experimental The experimental set-up for the deposit is described in the following (see Refs. [1,2] for more details). The films have been made by radiofrequency-powered magnetron sputter- ing onto electrical floating silicon substrates in a vacuum vessel. The deposition apparatus is shown in Fig. 1. The target was a pure sintered graphite disk (purity 99.995%). The target–substrate distance was fixed at 8 cm. In order to make ionized magnetron sputtering, the deposition system was equipped with a one-turn stainless steel coil (or antenna) placed at equal distance between the target and the substrate. After introducing the sputtering gas into the chamber at a pressure of 10 mTorr (argon for carbon films, a mixture of argon and nitrogen (50%/50%) for carbon nitride ones), the gas discharge was generated by applying an RF power (13.56 MHz, 150 W) onto the 5-cm-diameter graphite cathode. In order to follow the effect of the coil onto the film deposition, RF power can be injected in the antenna (150 W). This leads to two experimental deposition conditions: antenna Toffr (no power in the coil=standard magnetron deposition) and antenna Tonr (150 W in the coil: ionised magnetron sputtering). In the latter case, a very luminous plasma is obtained between the target and the substrate due to the energy supply of the coil to the magnetron plasma. After deposition, the samples were transferred into a Kratos Ultra Axis spectrometer for ex situ XPS analysis. 0040-6090/$ - see front matter D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.tsf.2004.11.172 * Corresponding author. Tel.: +33 1 49403488; fax: +33 1 49403938. E-mail address: ft@galilee.univ-paris13.fr (F. Te ´tard). Thin Solid Films 482 (2005) 192 – 196 www.elsevier.com/locate/tsf