Papers

ICMCTF2007 Session B2-1: Arc and E-Beam Coatings and Technologies

Monday, April 23, 2007 1:30 PM in Room Royal Palm 1-3

Monday Afternoon

Start	Invited?	Item
1:30 PM		B2-1-1 Bonding Network in Filtered-Arc-Deposited Carbon Films: Simulation and Characterization R. Gago (Universidad Autónoma de Madrid, Spain); I. Jiménez (Consejo Superior de Investigaciones Científicas, Spain); M. Vinnichenko (Forschungszentrum Rossendorf, Germany); A.Yu. Belov (Technische Universität Dresden, Germany); H.U. Jäger (Forschungszentrum Rossendorf, Germany) This work address the bonding structure of amorphous carbon films (a-C) with varying sp² content deposited by filtered-cathodic-vacuum arc (FCVA) at different substrate temperatures (up to 700K). Experimentally, the arrangement of carbon atoms within the atomic network is assesed by the combination of x-ray absorption near edge spectroscopy (XANES) and spectroscopic ellipsometry (SE) studies. The experimental evolution of sp² hybrids with temperature is contrasted with theoretical predictions from molecular-dynamics (MD) deposition simulations.
2:10 PM		B2-1-3 Filling Trenches on a SiO₂ Substrate with Cu Using a Hot Refractory Anode Vacuum Arc I.I. Beilis, D. Grach, A. Shashurin, R.L. Boxman (Tel-Aviv University, Israel) 100-nm-wide trenches were filled with copper, deposited by a radially expanding plasma plume from a hot refractory anode vacuum arc. The arc was sustained between a consumed water-cooled cylindrical Cu cathode (30 mm diameter) and a non-consumed cylindrical tungsten anode (32 mm diameter, 30 mm height) that was heated by the arc. An arc current of I=200 A was applied for periods of up to 180 s. The films were deposited on SiO₂ substrates having trenches with aspect ratio (depth: width) of 3:1. The substrates were exposed to the plasma plume while a shutter was open. Distance to the substrate was 100 mm from the electrode axis. A pulsed bias voltage of -100 V, 100 KHz and 50% duty cycle was applied to the substrate. The films were examined with a scanning electron microscope. The thickness of the film on the flat area was the same as for the trenches. The average deposition rate was about 0.2 µm/min (for a 120 s deposition starting 60 s after arc ignition).
2:30 PM		B2-1-4 Venetian Blind Filter System for Arc-Evaporation - Deposition of Nearly Droplet Free Hard and Wear Resistant Coatings for Cutting Tools S. Harris (Guhring Australia); F.-R. Weber (Konrad Friedrichs GmbH & Co. KG, Kulmbach Germany) Cathodic arc evaporation (CAE) is a widely used technique for generating dense, highly ionised plasma for the deposition of hard, wear resistant PVD coatings. As a result of the high degree of plasma ionisation, the good deposition rates and the relatively low cost of the power supplies, the process has been successfully commercialised by manufacturers of PVD coating equipment, especially in the area of coating deposition for metal cutting applications. A major drawback of CAE is the emission of micron-sized droplets of cathode material during the arc process which form defects in the subsequent coatings. While the presence of droplets prevents the exploitation of the arc evaporation processes in precision areas of optics, electronics and corrosion protection, the effect of droplets in PVD coatings used in cutting tool applications has previously been perceived to be less critical. However, more recently, the surface finish of PVD coated cutting tools has become increasingly important in the field of cutting applications, especially for High Performance Cutting (HPC), where smooth and low friction surfaces are required to prevent blockages and subsequent failure of cutting tools. Therefore we developed a venetian blind-filter system for an cathodic arc evaporation system to deposit smooth PVD coatings for improving the performance of cutting tools. The design and technical principle of the filter system is shown in this paper. The influence of the filter system on deposition rate and droplet reduction during the coating process will be explained. The Cathode melting temperature, the droplet solidification rate and the distance between the cathode and filter are important characteristics of the process which contribute to the filter efficiency.
2:50 PM		B2-1-5 Control of Film Composition Using Multiple Cathodes in a High Current Pulsed Arc: Synthesis of MAX Phase Alloys and Ti/C Multilayers J. Rosen, L. Ryves, P.O. Persson, D. McKenzie, M.M.M. Bilek (The University of Sydney, Australia) A new high current pulsed cathodic arc has been used for the synthesis of ceramic thin films and ternary alloys. An internally mounted curved magnetic filter is used to remove macroparticles from the plasma plume. We will discuss the optimisation of filter parameters and the use of multiple cathodes to enable film growth with predefined nanostructure and composition, controlled down to the level of an atomic percent. We describe the use of this system to deposit MAX phase films of Ti₂AlC, by means of alternating plasma pulses of sub-monolayer amounts of material, resulting in the 211 composition. Plasma characterisation using a Hiden mass selected ion energy analyser shows ion energies in excess of 100 eV, which together with substrate heating enable control of structural evolution. Another example which will be discussed is the deposition of Ti, C and TiC multilayers, by alternate powering of the Ti and C cathodes to control layer thickness and concentration, and hence properties such as hardness.
3:10 PM		B2-1-6 High Temperature Phase Changes and Oxidation Behavior of Cr-Si-N Coatings L. Castaldi (ETH and EMPA, Switzerland); D. Kurapov, A. Reiter (OC Oerlikon Balzers Coating AG, Liechtenstein); V. Shklover (ETH, Switzerland); P. Schwaller, J. Patscheider (EMPA, Switzerland) Compositional, structural and morphological studies were performed on Cr_xSi_yN_z coatings deposited by arc PVD on WC substrates. The systematic variation of the growth parameters resulted in a Si atomic concentration between 0 and 15 at. %, which affects significantly the structural and morphological properties of the coatings, their phase stability and oxidation resistance. All Cr_xSi_yN_z coatings consist of nanocrystalline CrN with crystallite sizes diminishing at increased Si content. The microstructure of the samples, observed by scanning electron microscopy, is columnar for the coatings with low Si concentrations, and becomes more dense and smooth for the specimens with higher Si content. X-ray powder diffraction studies were performed in situ at high temperatures in high vacuum (HV) and in the air. The coatings annealed in HV exhibit a good stability of the cubic CrN phase up to 1000°C. The temperature formation of the Cr₂N phase and the subsequent oxidation strongly depends on the composition and the morphology of the samples. The annealing performed in air proved an excellent oxidation resistance of the coatings. The best oxidation resistance was obtained for the samples with intermediate Si concentration, for which the formation of Cr₂O₃ or CrO₃ has not been observed even at 1000°C. The crystallite growth, which occurs at elevated temperatures both in HV and in air, becomes significant after approximately 800°C.
3:30 PM		B2-1-7 Deposition of Superhard CrAlSiN Thin Films by Cathodic Arc Plasma Deposition S.K. Kim, P.V. Vinh (University of Ulsan, Korea); D.B. Lee (Sungkyunkwan University, Korea); Y.H. Kim, J.Y. Lee (Korea Advanced Institute of Science and Technology, Korea) Thin films of CrAlSiN were deposited on AISI H13 tool steel substrate using Cr and AlSi cathodes by a cathodic arc plasma deposition system. The influence of the nitrogen pressure, AlSi cathodic arc current, bias voltage and rotation speed of the substrate holder on the mechanical and the structural properties of the films were investigated. The highest hardness level was observed at the deposition pressure of 4 Pa. The hardness of the films increased with the increase of AlSi cathode arc current. The hardness of the films reached 41 GPa at the bias voltage of -100 V and decreased with a further increase of the bias voltage. HRTEM investigation of the films showed that the films were consisted of multilayers of crystalline CrN and amorphous AlSiN. Wear tests were performed on the films deposited in various conditions.
3:50 PM		B2-1-8 Characterization of Quaternary Cr Based Nitride Films Synthesized by Cathodic Arc Method H. Hasegawa (Okayama University, Japan); T. Sato (Keio University, Japan); K. Ohashi, S. Tsukamoto (Okayama University, Japan); T. Suzuki (Keio University, Japan) It is generally recognized that thermal properties and thermal stability of nitride films are key parameters in designing the films, targeting engineering materials, used for diffusion barriers and wear protection. In previous works, (Cr,Al,B)N films were synthesized by the cathodic arc method, using Cr-Al-B alloy cathode by altering Z values from 0 to 0.10. It was found that adding B to Cr-Al-N ternary systems increases the micro-hardness while decreasing the lattice parameter of the resulting quaternary films, keeping cubic structures. In this study, quaternary Cr based nitride films deposited with addition of B, Si, Y were annealed in a vacuumed chamber at 800, 900 and 1000°C. Changes in micro-hardness and microstructure as a function of annealing temperature were studied and discussed based on X-ray diffraction method, electron microscopy and conventional micro-Vicker's hardness tests.
4:10 PM		B2-1-9 Syntheses and Mechanical Properties of Cr-Mo-Si-N Coatings by a Hybrid Coating System S.G. Hong (Pusan National University, Korea); D.-W. Shin (Gyeongsang National Uuniversity, Korea); K.H. Kim (Pusan National University, Korea) New Quaternary Cr-Mo-Si-N coatings have been deposited on stainless steel substrates (AISI D2) and Si wafers by a hybrid coating system combined arc ion plating (AIP) using Cr3Mo target and DC magnetron sputtering techniques using Si target in Ar/N2 gaseous mixture. The hardness of the Cr-Mo-Si-N coatings largely increased with Si addition compared to that of Cr-Mo-N coating. The high hardness of Cr-Mo-Si-N coatings was related to the composite microstructure consisting of fine crystallites and amorphous silicon nitride phase. The average friction coefficient of Cr-Mo-Si-N coatings gradually decreased with increase of Si content into Cr-Mo-N coatings. The microstructures of the coatings were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscope (HRTEM) in this work.