Leistungsfähige Dünnschicht‐Beschichtung für die Photovoltaik

High‐performance thin‐film coating for photovoltaic applications The thin‐film photovoltaics market is large and is expected to grow continuously. Due to its huge potential regarding cost reduction and cell efficiency improvement, sputter‐etched ZnO:Al‐based TCO can make a sustainable contribution to achieve grid parity. One of the most promising approaches here is the large scale volume manufacturing of sputter‐etched TCO glass for thin film silicon solar cells. VON ARDENNE's leading process knowhow, applied to the highly productive and reliable PIA|nova coating system, allows for cost effective production and flexible adaptation of customer specific TCO requirements.     

Verfügbarkeit von Metallrohstoffen für die Dünnschicht‐Photovoltaik

Availability of raw materials for the thin‐film photovoltaic on the example of gallium, indium and tellurium Gallium, tellurium, and indium are essential components used in the thinfilm technology which are predicted a growing demand. Their occurrence in the earth's crust is comparatively scarce thus they are produced and technically applied in small quantities. The trace metals are produced as a by‐product during extraction and refining of bulk metals such as aluminium, copper, or zinc. Essentially, the mining, processing and refining of the carrier element determines the maximum available production capacity. The global processing capacities of by‐products are limited, and the potentials of extraction are not fully utilized by current methods. Increasing the production of the by‐products would be achieved by increasing the production of the carrier elements or by extending the extraction capacities within an established production route. Moreover, the supply could be enhanced by processing currently untreated ores and concentrates as well as by treating residues from mining and processing.     

Plasmabeschichtungsverfahren für die Solarzellenherstellung

Photovoltaics, i.e. the conversion of light into electric energy, is an important link of the chain of regenerative energies, at which the further growing of the photovoltaic industry depends on the reducing of the costs from the manufacturing of the solar modules. Potential to reach the aim are cheaper basic material for the solar cells, as well as the reducing of the cost to manufacture cells and modules and the increasing efficiency of the solar cells. An essential process step during production of crystalline silicon solar cells is their coating with an antireflective and passivation layer. Amorphous hydrogenated silicon nitride (SiN) layers, deposited under vacuum by PECVD (Plasma Enhanced Chemical Vapour Deposition), have been demonstrated to be – besides good anti‐reflection layers – excellent means for surface and bulk passivation of silicon solar cells. Therefore they are especially effecting a significant increase of the conversion efficiency of multi‐crystalline silicon solar cells. With the common concept “SiNA” a series of effective, industrial scale systems for the SiN‐coating has been developed and qualified, caused by its excellent layer properties, high throughput, high up‐time and a maintenance‐friendly design. Consecutively performance parameters of the systems and relevant data of their use under production conditions are introduced.     

Werkzeugbeschichtungen für die Trockenbearbeitung

Tool coatings for dry machining During dry machining a strain collective consisting of mechanical, thermal, and chemical loads is imposed upon the cutting edge. Compared to conventional machining using cooling lubrication fluids, the loads are increased in dry cutting. A feasible solution to protect the cutting edge from thermal wear, abrasion, and tribo‐oxidation is the application of hard coatings. Newly developed Cr_xAl_yY_zN, Cr_xAl_yB_zN and Cr_xAl_ySi_zN PVD coatings were both evaluated in tribological model tests and machining tests concerning their suitability for dry cutting applications. Herein, the used coating technology and the coating properties are described in detail. The measured tool wear and the process forces give further hints for the optimization of the coating system.     

Materialien für die Vakuumbeschichtung

The main criteria for selecting a material for vacuum coating are discussed with respect to required film properties, selection of coating method and appropriate shape of the material. Production methodes are schematically presented together with an overview of quality control methodes of the final product.     

Zukunftsperspektiven für die Pulvermetallurgie durch die Betriebsfestigkeit

Future Perspectives for the Powder Metallurgy by Structural Durability Considerations The fatigue behaviour under complex variable amplitude loading cannot be simply assessed by knowledge of constant amplitude data. The peculiarity of variable amplitude loading, which occurs in almost all technical applications, is the possible frequent exceedance of the so called fatigue limit without reducing the required service life of the components. This fact which is described as structural durability enables a lightweight design of components and results in an aimed material exploitation. Thus, this advantage has not yet been considered in the design of PM parts. The paper discusses the suitability of PM steels for such complex service loadings and if the concept of structural durability may open new application perspectives.     

Innovative Technik für die Molekulardestillation

Innovative technique for molecular distillation Thermal sensitive materials as oils, fats, pharmaceuticals, vitamins a.o. can be separated into different fractions by applying the short path or molecular distillation. A new development combines the principle of the short vapor path with the plate falling film evaporator. A pilot unit will start operation in Spring 2010.     

Eine Thermovakuumkammer für die Weltraumsimulation

A thermic vacuum chamber is used for testing devices and components under space simulated conditions. We take a cryopump and a LN2 baffle for an oil free and vibration poor vacuum generation at pressures down to 3.10^?6 mbar. The surrounding temperature of the device under test can be varied between 83 K and 373 K by PC controlled shrouds. Temper areas simulate the influence of own and strange heatsources on the tested units. The actual behaviour of the device under test at different vacuum and temperature conditions can be observed via an optical window located at the chamber door. For these measurements there are two optical adjusting benches on both sides of the chamber door. The testing units are mounted in a clear room. A lot of optical and thermal measuring techniques as well as a mass spectrometer can be connected to the vacuum chamber. Because of different electrical and fluid feedthroughs at the chamber it can be used for a wide range of research task. The application of this thermic vacuum chamber is demonstrated at some examples.     

Automatisierte Plasmatechnologie für die Wirkstoffentwicklung

Automated Plasma Technology for Drug Development Processes The fast and economic development of new drugs and materials requires a high grade of automation. Beside biochemical test methods cell based assays such as proliferation, apoptosis or cytotoxicity assays are used for the testing of potential drugs against their biological activity. The use of cells is often connected with the requirement of strict sterile conditions and environments. This results in high investments and operating costs. The use of plasma for the sterilization of different surfaces has been demonstrated in a number of investigations. A suitable plasma source has been developed for the sterilization of micro titer plates used in biological screening processes. The integration of 96 parallel plasma sources into an special device enables the automated sterilization of micro plates in highly complex robot based screening systems. The system will be tested with different cell lines and assays.     

Elektrische Antriebe für die Raumfahrt

Electric Propulsion for Space Flight This article describes electric rocket motors for satellites, probes and manned spacecraft based on principles used for material processing, too. The need for high exhaust velocities is explained and the limitations of conventional chemical thrusters are pointed out. Two important electric propulsion technologies, arcjet thrusters and gridded ion thrusters, together with their applications are described. Both types are currently successfully operated in space. Finally, a hybrid engine using an arcjet thruster and propellant heating by radiofrequency power is introduced. This concept is a potential solution for the propulsion demands of a future piloted mission to Mars.     

Nanokristalline Diamantschichten für die Zerspanung

Nanocrystalline Diamond Coatings for Cutting Operations The history of the CVD diamond synthesis goes back into the fifties. However, the scientific and economical potenzial was only gradually recognized. In the eighties intensive world‐wide research on CVD diamond synthesis and applications were launched. Industrial products, especially diamond‐coated cutting tools, were introduced to the market in the middle of the nineties. The article shows the latest developments in this area, which comprises nanocrystalline diamond coating structures.     

Werkstoffkennwerte für die Lebensdauerberechnung von Strukturen aus Stahlfeinblechen für den Automobilbau

Materials Data for Fatigue Life Calculation of Steel Sheet Structures for Automotive Engineering Within a joint project of the steel and automotive industry 17 steel sheet materials for automotive engineering in various delivery and forming conditions at temperatures of –40 °C, 22 °C and 100 °C were investigated. In the course of 37 test series strain controlled fatigue curves to crack initiation and stress‐strain‐curves under monotonic and cyclic loading were determined. All experimental data, hysteresis loops and determined cyclic properties are available in a database. A correlation between the mechanical properties from tensile tests and the properties from strain controlled cyclic experiments seems to be possible.     

Magnetische Mikrokomponenten für die Mikroreaktionstechnik

Magnetic micro components for micro reaction technology Miniaturization and parallelization of chemical and molecular biological processes creates continuous demand for development of new micro scaled solutions. Arrays of reaction chambers with volume less than one micro litre were already developed, yet the biggest technical problem remaining is the handling and especially the transferring of substances in the range of nano litres between the reaction chambers. We have developed a new kind of magnetic beads enabling solid phase reactions and designed a new magnetic handling system and magnetic transfer carriers, that allow the parallel and selective substance transfer between miniaturized reaction chamber arrays with several thousand of chambers.     

Vakuumsysteme für die mobile Analytik

Vacuum systems for mobile applications Rising global pollution levels and therefore more stringent environmental regulations, the rising global danger regarding security in particular bombing attacks, drug trafficking and drug abuse, more precise prediction of natural desasters e.g. volcano eruptions and its effects to humans and air traffic, analysis of environmental effect from fracking, accidents in chemical and petrochemical plants, support police work in scouting offences, local leak detection on vacuum systems require portable and mobile analytical systems for in situ measurements. The article describes the requirements for the vacuum components and shows application examples for better understanding.     

Kollektorbeschichtungen für die EUV‐Lithografie

Collector Coatings for EUV Lithography Extreme ultraviolet lithography (EUVL) is the next generation lithogra phy method operating at the wavelength of 13.5 nm (14 times shorter than current lithography systems), enabling semiconductor scaling to resolutions of 22 nm and below [1]. This paper presents the successful coating of the world's largest ellipsoidal collector mirror for EUV radiation with a diameter of 660 mm ( Fig. 1 ). In order to achieve the required peak reflectivity of more than 65 %, the ellipsoidal collector was coated with a highly reflective, laterally graded multilayer using the dc magnetron sputtering system “NESSY”. A maximum reflectivity of the laterally graded multilayer of more than 65 % was achieved for radii smaller than 220 mm. For radii between 230 mm and 320 mm the reflectivity decreases to a minimum of 58 %. The targeted wavelength remains constant at (13.50 ± 0.05) nm over the entire collector surface which is well within the tight specifications for high volume manufacturing.     

Ionenbeschuss von Polymeren für die Medizintechnik

Ion Bombardment of Polymers for Biomedical Applications Ion implantation, a standard technology in the semiconductor industry, is also used since the 1960s for biomaterials. In the following, a variation of the method is presented for illustrative — plasma immersion ion implantation (PIII). In PIII treatments process times of less than a minute are found to be sufficient to change the surface energy at least for several weeks. In addition, a modified coefficient of friction, wear and topography can be obtained, with reduced wear rates and an increased roughness having a positive impact on the biocompatibility and the bioactivity. For combined coating and implantation processes with simultaneous energetic ion bombardment, an excellent adhesion is obtained even at room temperature. In addition to the formation of photo‐active surfaces, which may have an antibacterial effect here also an osteoinductive topography can be achieved.