Dünne Schichten durch Deposition unter streifenden Einfall

Micro‐ and nanostructured thin films by Glancing angle deposition Physical vapour deposition under conditions of obliquely incident flux and limited adatom diffusion results in films with a columnar microstructure. These columns will be oriented toward the vapour source. An additional substrate rotation can be used to sculpt the columns into various morphologies (slanted and vertical posts, chevrons, screws or spirals). With this glancing angle deposition (GLAD) technique can prepared porous thin films with engineered structures from a variety of dielectric, semiconducting and metallic materials. The paper presents the In this paper the physical fundamentals of the GLAD technique are introduced, the production of micro‐ and nanostructures of different morphology on non‐patterned and patterned substrates is demonstrated and some possible applications of this new deposition technique are introduced.     

Dünne Schichten für die Optik und Kristallherstellung in Oberkochen von 1946 bis heute

Thin films in optics and the growing of optical crystals are strongly related to the high vacuum technology. The development of this technology by Carl Zeiss at Oberkochen since 1946 until now is reported in this paper.     

Steuerung der Benetzungseigenschaften von optisch transparenten Polymeren durch Antireflexstrukturen und dünne Schichten

Controlled wetting of optical polymers by antireflective structures and thin films The wetting behaviour of antireflective structures can be modified by additional coatings to become superhydrophobic or hydrophilic. The sub‐wavelength structures which increase the samples transmission are generated by plasma etching. Bump structures with large aspect ratio show a Lotus‐like behaviour immediately after coating with a thin hydrophobic layer. In case of PMMA the Lotus‐state can only be achieved if a thin silica layer is arranged below the hydrophobic top‐layer.     

Optisch dünne Schichten aus Sicht eines Anwenders

Optical thin films are used for example, in precision optics. Their effect is important for lenses with many elements. In special plants, materials are evaporated in order to deposit to a thin film on substrates. Cleaning before and smoothing after deposition are also steps in thin film production. Because of its advantages, ion-assisted deposition of cold substrates overcomes conventional physical vapour deposition of heated substrates.     

Dünne ITO‐Schichten als leitfähige,transparente Elektroden. Thin films of ITO as conductive,transparent electrodes

This article deals with materials science aspects of In₂O₃:Sn (“ITO”) coatings and with the process technology of variants of sputtering used to obtain thin films with properties desired for specific applications. As an example, antistatic and antireflective coatings of monitor tubes are presented. The influence of sputter parameters such as substrate temperature, plasma excitation mode, sputter pressure and oxygen partial pressure on the quality of the films is discussed. It is shown how application‐oriented basic research helps to obtain recipes for materials design. Two basic aspects are discussed in more detail: the influence of an oxygen surplus in the films on microstructure and electrical properties and the correlation of electrical and optical parameters of the films.     

Optisch dünne Schichten mit kontrollierten Eigenschaften durch plasmaunterstütztes Magnetronsputtern

Optical thin films with controlled properties by plasma enhanced magnetron puttering A new reactive magnetron sputter process was investigated in which an additional plasma source was implemented to support the magnetron sputter process. The plasma source is determined by high ion current density and moderate ion energy. At the beginning of the work, extensive investigations of the interaction of the magnetron with the plasma source during the deposition process were performed. Also, the plasma parameters in the region of the substrate were determined. A stable process which can be controlled very precicely was obtained with the set‐up used here. In the following, different oxide materials such as zirconia (ZrO₂) and titania (TiO₂) were deposited and investigated. It shows that because of the precise process control, different optical and morphological properties can be directly influenced by tuning the ion‐to neutral fraction of the process.     

Nanostrukturierte dünne Schichten mit Giant Magnetoresistance (GMR) Effekt für Sensoranwendungen

Nanostructured Thin Films with Giant Magnetoresistance (GMR) Effect for Sensor Applications The basics of the Giant Magnetoresistance (GMR) effect in thin films prepared by evaporation in ultra high vacuum or by sputtering are explained and different GMR‐systems are presented. Applications of the GMR and the related TMR (Tunneling MR) effect can be found in sensor applications as well as in information and data storage technology.     

Virtuelles Werkstoff‐ und Prozessdesign funktionaler Schichten

Virtual Material‐ and Processdesign of Functional Coatings Thermally sprayed and plasma transferred arc clad coatings are often used to improve the surface properties of mechanical parts with regard to an improved wear and corrosion behavior. New coating processes and applications can be developed, if it is possible to control the coating microstructure by a defined management of the process parameters. Simulation can be used to get a detailed understanding of the process‐material interaction for a defined controlling of the process parameters with less experimental effort. This allows a systematic variation of the coating structure and to calculate the parameter set which represents the best compromise between a high deposition rate and low residual stresses in the coating. In order to model thermal spraying, the following sub‐processes are considered: gas flow, material supply, heating and accelerating of particles, particle impact on the substrate, coating formation, solidification and formation of residual stresses. The results presented in this paper will demonstrate the influence of the process parameters on particle properties and subsequently on the splat formation, the coating formation and the coating microstructure. Controlling different process parameters like material injection conditions and substrate properties, the heating, cooling and solidification behavior of the particles and the coating structure can be influenced significantly.     

Schichten über Schichten

Films over films: innovative coatings for complex applications Thin films and coatings have developed as a prerequisite for many technical applications. In this paper, some applications for electrical, electronic, biomedical and optical applications are presented. In this contribution, examples for coatings for conductive and transparent films in photovoltaics, films for biomedical electrodes, for semiconductor contacts and for high‐temperature contacts are presented and discussed. The films are prepared by magnetron‐sputtering and pulsed laser deposition. The influence of the processing parameters on the functional properties of the films is presented.     

Gasflußmessung mit Blenden und Düsen

The amount of gas flowing through a duct can be measured by inserting a constriction and detecting the pressure drop at the constriction. In the case of ideal flow conditions, the relation between gas flow and pressure drop can be calculated from fundamental principles. In practical operation, however, disturbing effects have to be considered. The various types of constrictions (orifice, short nozzle, Venturi nozzle) exhibit different characteristics. In the laboratory for vacuum technology of the Fachhochschule in Giessen several rigs for measuring the gas throughput by means of the pressure drop principle have been installed. The characteristics of these rigs have been determined by calibration using primary methods. The apparatus allows the measurement of gas throughput in the range 10^?7 bis 10⁵ mbar · l/s.