Lichtbogengestützte Prozesse zur Beschichtung von Kunststoffen

In the past ten years plasma enhanced deposition techniques have gained much increased importance due to the possibilities of improving and developing new film properties. Among these properties are adhesion and film structure. One of the new plasma assisted film deposition techniques is the Arc enhanced thermal evaporation technique. This new deposition technique and the film properties that are possible with this technique and its applications are described in this paper.     

Abscheidung optisch,elektrisch und akustisch wirksamer Schichten mit dem Doppel‐Ring‐Magnetron

Numerous applications in optics, electronics and sensor technology require thin dielectric films. Conventionally they are deposited by evaporation, activated evaporation, rf‐sputtering or CVD‐techniques. This paper describes the deposition of such films using reactive Pulse Magnetron Sputtering. This technology not only enables a tenfold deposition rate compared to the conventional techniques but also offers new possibilities for influencing film growth. For example it is possible to alter film composition during deposition and hence to deposit complete optical systems without interruption of the plasma process. Furthermore the energetic bombardment of the growing film can be controlled in a wide range by the pulse mode and the pulse parameters. This can be used to either deposit very dense films by strong energetic bombardment or to deposit films at low thermal load onto temperature sensitive substrates. Examples of film deposition for laser optics, electrical insulation applications and surface acoustic wave devices show how these new technological possibilities advantageously can be used for creating innovative layer systems. Film deposition is carried out in stationary mode using a Double Ring Magnetron. This type of magnetron ensures film thickness uniformity better than ± 1 % on 8” substrates by the superposition of the thickness distributions of two concentric discharges.     

Materials processing by gas cluster ion beams

This paper discusses the principles and experimental status of gas cluster ion beam (GCIB) processing as a promising surface modification technique for practical industrial applications. Theoretical and experimental characteristics of GCIB processes and of related equipment development are described from the moment of neutral cluster formation, through ionization, acceleration and impact upon a surface. The impact of an accelerated cluster ion upon a target surface imparts very high energy densities into the impact area and produces non-linear effects that are not observed in the impacts of atomic ions. Unique characteristics of GCIB bombardment have been found to offer potential for various industrial applications that cannot be achieved by conventional ion beam processing. Among prospective applications are included shallow ion implantation, high rate sputtering, surface cleaning and smoothing, and low temperature thin film formation. Sputtering effects produced by cluster ion impact are particularly interesting. High sputtering yields and lateral distribution of sputtered atoms cause surface smoothing effects which cannot be achieved with monomer ion beams. Surface smoothing to atomic levels is expected to become the first production use of GCIB.     

Großflächige Quellen f�r die industrielle Plasmatechnik

Plasma‐technological processes in modern thin film technologies for the refinement of surfaces are of constantly growing interest. Plasma‐technical procedures for the surface modification and film deposition mainly are contributed to the low pressure regime and use ion and/or plasma techniques. In particular plasma‐technological process concepts in the industrial field require adapted and scalable large area plasma sources. A new source concept, based on a coaxial structure, unites these specifications and permits plasma arrangements of nearly any required size.     

Plasma und Dünne Schichten

Plasma and thin films for lighting application Thin films play an important role in the lighting industry. Well known products are reflectors with simple aluminium coating or with dichroic coatings for cold light mirrors. Especially for energy saving applications special halogen bulbs are coated with a transparent hot mirror that increases the overall efficiency up to 50 % while keeping the positive properties of halogen lighting like color, color rendering index, start up performance and others unchanged. Special thin film applications realize color filters, IR filters, UV filters or color conversion filters. All these processes are vacuum processes that work with plasma assistance. The most prominent technologies for cost effective production are the PICVD processes (former development of SCHOTT AG in cooperation with Auer Lighting) and the Microdyn® technology from DSI, Santa Rosa.     

Plasmatechnik in der Photovoltaikindustrie

Application of Plasmatechnology in Photovoltaic Industry Ever since the introduction of attractive feed‐in tariffs for photovoltaic electricity generation, there has been a huge surge in all kinds of photovoltaic applications. Products based on multicrystalline wafers still have the largest market share with thin film products picking up in recent times. Manufacturers of thin film products have increased their production volume. In the meantime, production technology for wafer based solar cells has been improved. With the second generation of tools a trend towards standardization is to be noticed. Both in wafer based as well as in thin film solar cells a number of plasma processes are applied in the production process. These processes include conventional magnetron sputtering or PECVD as well as plasma chemical etch processes. In terms of thin films the portfolio ranges from the rather well known silicon nitrid or ITO films to rather more complex binary films. We will present but a few examples from the afore mentioned applications and discuss open question with respect to vacuum and machine technology.     

MASS SELECTED ION BEAM DEPOSITION: A TOOL FOR PARAMETRIC GROWTH STUDIES, PROCESS DEVELOPMENT AND FABRICATION OF DIAMONDLIKE FILMS

Diamondlike films have unique properties that can be tailored between those of diamond and those of graphite to meet industrial applications. The purpose of this review is to emphasize the ability to prepare films with specific properties through control of the deposition parameters. The three basic approaches, plasma deposition, chemical vapor deposition, and ion beam deposition, are presented. Since the first two methods consist of complex chemical-physical systems which limit the possibilities for controlled parametric studies, the focus herein is on the latter technique. This work presents the unique capabilities of mass-selected carbon ion beam deposition in controlling deposition parameters over a wide range, particularly when combined with in-situ analysis of film evolution. The role of different deposition parameters on diamond film growth is discussed. The Houston deposition system that manifests the above features is described. A summary of results of some ongoing experiments is given to demonstrate the system capabilities for both parametric studies of diamondlike film growth and actual production of diamondlike films.     

Plasmamessungen und Schichteigenschaften

Plasma Analysis and Thin Film Properties of Sputter‐ and Ionplating PVD‐Processes For a large number of thin film applications just few thin film coating processes are used in industrial scale production. For example, Magnetron Sputtering (MS), Ionplating (IP), Arc Source Ablation (AS) and technical variations of them. Recent developments allow beside traditional dc modes also the use of pulsed dc modes, as for instance in magnetron sputtering and arc source deposition. In this work the Reactive Low Voltage Ionplating (RLVIP) with pulsed substrate bias (Ionplating Plasma Assisted IPPA), DC and DC‐pulse Magnetron Sputtering and Arc source deposition in DC‐ and DC‐pulse mode is of interest concerning their plasma. Pulsing the substrate‐bias of the RLVIP (IPPA) influences film stress and optical absorption but is not easy to handle in industrial production. Pulsing the sputter processes leads to massive changes in the coating plasma and the coatings itself. And finally pulsing the arc‐current of the Arc Source Ablation processes implements advantages for lower cathode temperatures, for use of less conducting cathode materials, less droplet formation and improved chemical reactivity with oxygen.     

1.13 Plating with ion accelerators

Formation of thin films by sputtering and ion plating are well-known techniques. The present contribution describes ion beam plating which is a novel technique somewhat related to ion plating. Thin films of metal compounds on a substrate are decomposed by ionic bombardment resulting in films with good adherence to substrate. The formation of thin palladium films on silicon surfaces will be discussed in detail. Halide compounds of palladium dissolved in organic solvents are sprayed onto the substrate. Subsequently these thin films are exposed to ion beams of inert gases in the energy range below 100 keV. After ion exposure, remains of the halide compound are removed chemically. The ion beam plated film, which appears mirror-like, is then investigated by scanning electron microscopy, proton back-scattering in order to characterise the ion beam plated film. The possible applications of ion beam plated films will be discussed.     

UV‐Lasertechnologie in der PLD

Future of UV Lasertechnology in industrial PLD processes The success formula for any thin film technology on the production floor is bridging the gap between precisely depositing a functional thin film and at the same time achieving industrial processing rates. Fortunately, the pulsed laser deposition method has come of age thanks to output power and stability advances in UV excimer laser technology and has become a proven and industrial grade thin film deposition method.     

Herstellung von Präzisionsschichten mittels Ionenstrahlsputtern

Precise thin film synthesis by ion beam sputter deposition Ion beam sputter deposition (IBSD) is a promising technique for the fabrication of high performance thin films because of the well defined and adjustable particle energies, which are rather high in comparison to other PVD techniques. Recent developments concerning long‐term stability and lateral uniformity of the ion beam sources strengthen the position of the IBSD technique in the field of precise thin film synthesis. Furthermore, IBSD offers a more independent choice of relevant deposition parameters like particle energy and flux, process gas pressure and deposition rate. In this paper we present our currently installed large area IBSD facility “IonSys 1600”, which was developed by Fraunhofer IWS Dresden and Roth & Rau company (Hohenstein‐Ernstthal). Substrate sizes of up to 200 mm (circular) or up to 500 mm length (rectangular) can be coated and multilayer stacks with up to six different materials are possible. Tailored 1‐ or 2‐dimensional film thickness distributions with deviations of < 0.1 % can be fabricated by a relative linear motion of the substrate holder above an aperture. In order to demonstrate the advantages of the IBSD technique especially for sophisticated materials and films with high requirements concerning purity, chemical composition or growth structure, several examples of deposited multilayers for various applications are presented.     

Plasma-based processes and thin film equipment for nano-scale device fabrication

Plasma-based thin film equipment and processes have been widely used for micro-electronics, information storage sensors, and energy harvest/storage devices. To achieve higher package density, large storage capacity, and to meet other specific stringent design criteria, the film layer thickness is often reduced to a few nanometers or even to a few angstroms, while the device dimension has been shrinking to sub-micrometer scales. As the material thickness (h) approaches atomic dimension and the device dimension (w × d) approaches a few tens of nanometers, thin film layer uniformity and inter-layer mixing, as well as device edge damage control are crucial for its performance and reliability. In this review paper, we will discuss briefly vacuum and plasma aspects, followed by a detailed review on various plasma-based thin film deposition and removal techniques. The deposition methods discussed here include magnetron sputtering, ion beam deposition (IBD), and plasma enhanced chemical vapor deposition (PECVD). We focus on the advantages and disadvantages of various hardware configurations and how to achieve uniform film growth over large area with minimized interlayer mixing for any specific process. The device patterning aspects cover ion beam etching (IBE), reactive ion etching (RIE), and various techniques for end-point detection of etching processes. We discuss how the definition technique affects edge damage, profile, and dimension (w × d) control, as well as post-definition corrosion behavior. Some specific examples will be presented to highlight how the physical principles can be used in practice for film/device property control.     

微波电子回旋共振等离子体技术及其应用

微波电子回旋共振等离子体是淀积薄膜、微细加工和材料表面改性的一种重要手段。由于这种等离子体电离水平高,化学活性好,可以用来实现基片上薄膜的室温化学气相淀积和反应离子刻蚀,因此对于微电子学、光电子学和薄膜传感器件的发展,这种等离子体会具有重要的意义。此外,采用微波电子回旋共振等离子体原理,没有灯丝的离子源可以提高离子源的使用寿命,可以增加离子束的束流密度。可以确信,微波电子回旋共振等离子体的发展,将把离子源技术提高到一个新的水平。显然,这必将对材料表面改性工艺,包括离子注入掺杂等工艺的发展发挥作用。自从1985年以来,为了得到大容积等离子体而发展了微波电子回旋共振多磁极等离子体,这些技术在薄膜技术、微细加工以及材料表面改性中的应用前景是乐观的。我们将在本文中,介绍微波电子回旋共振等离子体的原理及其应用。     

A comparison of three techniques for measuring strain at feature of thin film materials

Good knowledge of the mechanical properties of thin film materials is important for reliable design of advanced electronic packages such as multi-chip modules (MCMs). Strain at fracture is one of the important properties which has not been well characterized for some of the candidate thin film materials for MCMs. In part, this is due to the lack of simplw and accurate techniques to measure strain at fracture of thin film materials. Two new techniques have been developed to alleviate this problem. The first is an acoustic technique in which an accelerometer is attached to the film. The film is then gradually strained and when the film fractures, an acoustic wave propagates through the film thereby creating a transient signal from the accelerometer. This signal is used to trigger an oscilloscope. The second technique is similar except that it utilizes a laser probe to detect the acoustic wave. In this photo-acoustic method, the laser is reflected from the film onto a bisectional photodetector while the film is gradually strained. Upon film fracture, the acoustic wave modulates the laser beam and a transient voltage pulse is produced by the photodetector. Both techniques are capable of detecting the formation of extremely small cracks. The two techniques are compared with a previously reported electrochemical technique. All three techniques are accurate, simple to implement, and inexpensive but have relative advantages and disadvantages.     

Mikrowellen‐PECVD für kontinuierliche Großflächenbeschichtung bei Atmosphärendruck

Microwave PECVD for continuous wide area coating at atmospheric pressure Plasma processes are applied for a variety of surface modifications. Examples are coatings to achieve an improved corrosion and scratch protection, or surface cleaning. Normally, these processes are vacuum based and therefore suitable to only a limited extend for large area industrial applications. By use of atmospheric pressure plasma technology integration in continuously working manufacturing lines is advantageously combined with lower costs and higher throughput. Microwave plasma sources present powerful modules for plasma enhanced chemical vapour deposition at atmospheric pressure. At Fraunhofer IWS processes and equipment as well as application specific materials are developed. The coatings are suitable for scratch resistant surfaces, barrier and corrosion protective layers or anti‐reflex layers on solar cells. The film properties achieved are comparable with those produced by low pressure processes.     

IonScan 800 – Ultrapräzise Schichtdickenkorrektur für die Halbleitertechnologie

IonScan 800 – Ultra precise Film Thickness Trimming for Semiconductor Industry Many applications in semiconductor technology are characterised by extreme requirements in terms of film thickness homogeneity. When manufacturing Bulk Acoustic Wave (BAW) components, it is necessary to adjust film thickness values of different materials with accuracy values in the nm‐range. Standard processes, such as the film deposition techniques, do not fulfil these homogeneity requirements. Thus it is necessary to perform a local correction of the film thickness in a follow‐up process. The authors here introduce a new method of local film thickness trimming and its technical implementation. During the process, the wafer is moved in front of a focussed ion beam. The local milling rate is controlled upon the residence time of the ion beam at certain positions. A modulated velocity profile is calculated specifically for each wafer, in order to mill the material at the associated positions to the homogenous target film thickness. Depending on whether an inert or reactive ion beam process is used, it is possible to apply the IonScan technology for any material desired, such as Si₃N₄, SiO₂, Al₂O₃, AlN, W, Mo, Cu or NiFe.     

Verwendung kalter Plasmen in Schichtherstellungsprozessen

Plasma deposition techniques are strongly required in high-quality thin film production. In this paper an attempt is made to describe shortly fundamental properties of cold plasmas and to inform about their technical generation. The growing industrial applications of plasma in various PVD- and CVD-technologies for coating and for surface cleaning as well as for chem. modification and structuring of surfaces and films are reviewed. Finally an example is given about plasma surface treatment of plastic car bumpers before lacquering.     

Gefilterte Bogenbeschichtung – alte Probleme und neue Lösungen

Currently, the vacuum arc deposition (VAD) technique is well established in industry, primarily to deposit wear protective hard coatings such as metal nitrides and carbides onto tools and components. From the beginning of the industrial development of the vacuum arc deposition, it was obvious that the emission of macroparticles or droplets is a fundamental drawback of this coating technology. The emission is caused by the highly dynamic process of plasma generation and limits the fields of application significantly. Different methods have been proposed to minimize the macroparticle flux to the substrate surface. But the only way to hinder droplets from reaching the substrate reliable is to separate the plasma from particles by using curved magnetic fields. This filtered arc technique has proven its superiority of depositing high quality films compared to conventional arc applications in numerous laboratory tests. Current demands have stimulated new developments at the Fraunhofer IWS of more compact and higher productive filtered arc sources. One important application of ultra thin protective films is the topcoat on hard disks. In order to increase the storage density, the head‐to‐media spacing as well as the thickness of the overcoat has been reduced continuously. Until now, the thickness of the sputtered films was reduced to about 4 nm. The limit for this technology seems to be achieved. Filtered arc deposition is one of the most promising candidates for the deposition of thinner films – down to 1.3 nm with an even improved mechanical and chemical resistance. Another application area is the manufacturing of metallic lines and interconnections with high aspect ratios in the deep sub‐micron region in microelectronics. The excellent properties of this new filtered source for the deposition of conducting lines in microelectronics were been demonstrated. Actually, the technology for the subsequent deposition of barrier films and conducting wires is under development. Besides the micro technologies, there are a lot of applications requiring higher quality but not (yet) such a perfect film surface. Therefore, using a quite simple filter design – the so‐called Venetian blind filter – a filter unit was developed which can be used at the common industrial vacuum arc deposition machines. The filter does not reduce the deposition area, so the standard deposition processes can be used furthermore. With this filter, the number of droplets can reduced dramatically. A plasma transmission through the filter of approximately 20 % could be measured. Such filter module was realized and is in use now.     

EPMA‐Analyse dünner PVD‐ und CVD‐Schichten

EPMA analysis of thin PVD and CVD layers Electron Probe Micro Analysis (EPMA) is an X‐ray spectroscopic method for determining the chemical composition of solid substances in the near‐surface region. It has a high detection sensitivity, a high spatial resolution, an adjustable depth of analysis and is easy and accurate to quantify. Less well known is the fact that the EPMA is also able to analyze the chemical composition and layer thicknesses of thin multi‐layer systems non‐destructively and with only one single measurement. In particular, it is possible to determine, for example, the composition and thickness of a layer buried under one or more other layers. Conversely, with a known film thickness, the density of thin layers can be determined, a quantity that is generally difficult to access with thin layers. The following article describes the physical basics of EPMA analysis and compares them with energy dispersive X‐ray spectroscopy (EDX) and X‐ray fluorescence analysis (XRF), which are also widely used. The principle of so‐called thin film analysis for multilayer systems is explained, and the possibilities and limitations of this method are illustrated by a number of industrial application examples.