Papers

ICMCTF1999 Session G6: Large-area Production Coatings for Webs/Plasma Cleaning and Pretreatment of Large Surfaces

Wednesday, April 14, 1999 8:30 AM in Room Town & Country

Wednesday Morning

Start	Invited?	Item
8:30 AM		G6-1 Pulse Duration Effects in Pulse-Power Reactive Sputtering of Dielectrics Using a Dual Magnetron. A. Belkind, A. Freilich, Z. Zhao (Stevens Institute of Technology); R. Scholl (Advanced Energy Industries) Reactive sputtering of dielectrics is suffering from two problems: arcing on the target surface and anode disappearing. Both problems have caught lately serious attention. One way to solve them simultaneously is to apply pulsed power alternately to a set of two magnetrons. Although this approach has been already implemented, a detail investigation of it is lacking. In this work, pulsed power reactive sputtering from a dual magnetron system is studied. The effects of pulse durations, gas pressure, and discharge current on reactive sputtering of aluminum oxide are experimentally examined and optimum conditions determined. Results are analized and discussed.
8:50 AM		G6-2 Sol-Gel-Processing of Functionalized Coatings Based on Inorganic-Organic Polymer (ORMOCER_âs) K.-H. Haas, S. Amberg-Schwab, K. Rose, G. Schottner (ISC, Würzburg, Germany) Hybrid polymers (ORMOCER_âs) with inorganic and organic structural units are used to generate special functionalized coatings on a variety of substrates (ceramics, metals, polymers etc). By processing at temperatures below 150 °C the formation of both inorganic and organic network structures using a wet-chemical process (sol-gel approach) is possible. The incorporation of special organic functional groups leads to important application related properties. ORMOCER_â-lacquers can be processed by nearly all conventional coating techniques (dipping, spraying, spin on etc) and cured by thermal or radiation energy. The basic properties and applications of ORMOCER_â-coatings are: _* abrasion resistance, _* barrier layers (foodstuff packaging), _* chemical resistant decorative layers, _* corrosion resistance, _* antisoiling, antifogging, antistatic and antireflective applications. Some examples are presented in detail. Vapor deposited inorganic thin films (SiO_x, AlO_x) in combination with ORMOCER_â-layers show very promising properties for high-performance barrier applications..
9:30 AM		G6-4 PVD Hard Coats on Plastics N. Schiller, V. Kirchhoff, H. Morgner (FEP, Dresden, Germany) The production of transparent Hard Coats is of importance for a wide range of applications. Up to now, the so-called Wet Coat process has predominated. Comparing Web and PVD Hard Coats with respect to such important characteristics as hardness and abrasion resistance explains the importance of PVD Hard Coats employing materials such as Si oxides and Al oxide. PVD Hard Coats have superior hardness and abrasion resistance, though production costs for the different processes must be considered. It will be shown that the Hollow Cathode Activated Deposition (HAD) Process permits coatings with a high degree of hardness and good abrasion resistance at high coating speeds. The fundamental features of the HAD process will be explained with particular attention given to production costs, and including relationships between layer characteristics and production parameters. The links between productivity, coating speed, layer thickness and costs will be discussed. Taking its production costs and characteristics into account, the PVD Hard Coat will become of outstanding industrial significance.
10:30 AM		G6-7 Rod Cathode Arc Activated Deposition (RAD): a New Plasma Activated Electron Beam PVD-process Chr. Metzner, B. Scheffel, K. Goedicke, J.-P. Heinss (FEP, Dresden, Germany) The paper presents a new plasma activated PVD-process - the so called Rod cathode arc Activated Deposition (RAD) process. This process is designed for high rate electron beam evaporation in the power range of 50 - 300 kW and is well adapted to large area deposition. The plasma is generated by an arc discharge embedded in the vapor stream of evaporated material. An additional hot rod-shaped electrode is used as cathode of the arc discharge. The electrode is heated by a part of the power of the electron beam. Our most actual results in process development are presented in this paper. The RAD-process is demonstrated on the hand of deposition of stainless steel coatings by ion plating. A high deposition rate in the order of 0.1 - 2 micro-meter per second µmm s^-1 and an intensive ion bombardment with an ion current density of 10 - 100 mA cm^-2 have been measured on the substrate. The relations between film properties and the process parameters will be shown. Finally, an outlook of the potential applications of technologies with a rough estimation concerning the process cost will be presented.
10:50 AM		G6-8 New Properties of Galvanized Steel Sheets by High Rate Electron Beam Deposition Chr. Metzner, B. Scheffel, F.-H. Roegner (FEP, Dresden, Germany) High rate electron beam evaporation is the most powerful PVD-technology for low coating cost on metallic sheets or strips. New fields of application have been revealed by using additional dense plasma. A new coating technology was developed for improvement of forming, varnish adhesion and corrosion protection properties of galvanized steel sheets. Several layer systems have been produced by electron beam evaporation with a high deposition rate (about 1000 nm s^-1). New properties of the coatings can be only obtained by a following special in-line vacuum heat treatment. A indispensable precondition for the successful formation of the coating is a pre-treatment with an in-line dense plasma process. The process parameters of pre-treatment, high-rate electron beam deposition and heat treatment also concerning time cycle define sensibly the properties of the coating in a wide range. Best results can be obtained in an in-line mode. FEP has the possibility to produce such coatings nearly under industrial like conditions in the near future. Finally, an outlook of the potential industrial applications of the technology with a rough estimation concerning the process cost will be presented.
11:10 AM		G6-9 Different Pulse Techniques for Stationary Reactive Sputtering with Double Ring Magnetron P. Frach, H. Bartzsch (FEP, Dresden, Germany) Double ring Magnetron (DRM) sources are best suited for stationary uniform coating of large substrates with metals, alloys and compounds. Even highly insulating oxides and nitrides have been deposited with high rates onto 8 inch substrates. DRM sources are characterized by two concentric discharged on electrically insulated targets. Therefore different mf pulse techniques can be applied: (I) a voltage with alternating polarity between the inner and outer target (bipolar mode) (II) a pulsed dc voltage for both of the targets (unipolar mode). It will be shown that process parameters like energetic ion flux towards the substrate and thermal load as well as layer properties like mechanical stress and hardness are influenced by pulse technique and parameters.
11:30 AM		G6-10 Electron Beam Curing of Three Dimensional Parts S. Schiller, G. Mattausch (FEP, Dresden, Germany) The importance of electron beam curing for industry is steadily growing. The call for environmentally beneficial production technologies not utilizing solvents as well as the increasing demands regarding surface properties, like hardness, scratch and light resistance, can be considered as stimuli for this development. The chemical and physical basics of electron beam curing are well known for many years. However, accelerating voltages above 200 kV are typical for the technologies and plants established up to now. It is one goal of the lecture to outline the benefits that result from the use of accelerating voltages below 150 kV. In the recent time, the electron beam curing utilizing robots was introduced into the industrial production. This completely new development enables the curing of three-dimensionally shaped parts for a great variety of applications. A specially constructed electron beam gun, which can be handled by robots, is described in the second part of the lecture. Practical examples are discussed. In addition, technical and economical data of the new technology are reported.
11:50 AM		G6-11 Two dimensional Electron Beam Curing and Crosslinking S. Schiller, O. Roeder, S. Panzer, R. Bartel (FEP, Dresden, Germany) The curing of organic coatings like varnishes, sol-gels, and similar things by heating and UV-radiation is an established technology. The thermal processes are connected with use of solvents. Such solvents cause pollution and ecocide. Therefore, they are criticized more and more. For utilizing of UV-curing, photosensitive additives have to be used. Such additives are problematic in the case of outdoor applications. When using electron beam curing, neither solvents nor photosensitive additives are necessary. As a result, a better quality of coatings, especially in the case of outdoor applications, is achieved. The still existing reservations against electron beam curing can be overcome by employing acceleration voltages in the range of 90 - 120 kV. This will pave the way for the broader dissemination of electron beam curing applications . In the lecture, a family of systems for electron beam curing of coatings on two-dimensionally shaped substrates is introduced. The main fields of application, like laminates, wood products, window films, tiles, as well as sterilization of surfaces, are discussed considering both, technical and economical aspects. The same family of systems can be used for crosslinking, too. Significant improvement of temperature resistance, shrinkage behavior, tear propagation and strength can be obtained. Finally, an overview of fields of applications today and in future is given.
12:10 PM		G6-12 Deposition of Thick High Adhesive Conductive and Protective Films on Dielectrics S.P. Bugaev, N.S. Sochugov, A.N. Zakharov (Institute of High Current Electronics Siberian Division of the Russian Academy of Sciences, Russia) Surface modification of dielectrics and deposition of different coatings make possible to extend fields of theirs applications, and to apply them for unusual purposes. We had realized a process of deposition of thick conductive and protective oxide films on the variety of substrates (glass, ceramics, polymers, etc.). This process based on unique method for increasing of coatings adhesion to substrates. The coating deposition is performed in vacuum chamber with plasma generator and DC-magnetrons. During the first stage of the process substrates are treated, cleaned and modified by plasma of the stationary diffusive arc discharge. It leads to excellent adhesion of coatings to substrates. Metal film deposition is performed by DC-magnetron sputtering of metal target in argon atmosphere. Oxide layers deposition is performed by DC-magnetron sputtering and using separated inert and reactive gases inlets. The films grow rate was the following: for metal films (Cu, Al, Ti, stainless steel) up to 0.2 µmm/min; for oxide films (TiO₂, Al₂O₃) up to 0.1 µmm/min. Thickness of films was up to 10 µmm. Microhardness of alumina films was 1000 kg/mm². The process of conductive coatings deposition on components of microwave devices made of polyethylene was elaborated both for industrial and for laboratory needs. Microwave characteristics of coated polymer components were close to those of metal components. This substitution allows to reduce cost of device. The main characteristics of copper films deposited on the polyethylene substrates was the following: electrical resistivity is 5E-8 Ohm*m, adhesion up to 40 kg/cm².