Fraunhofer Institute for Electron Beam and Plasma Technology

Germany

Fraunhofer Institute for Electron Beam and Plasma Technology

Germany
SEARCH FILTERS
Time filter
Source Type

Scheffel B.,Fraunhofer Institute for Electron Beam and Plasma Technology | Zywitzki O.,Fraunhofer Institute for Electron Beam and Plasma Technology | Metzner C.,Fraunhofer Institute for Electron Beam and Plasma Technology
Surface and Coatings Technology | Year: 2017

Some applications in energy technology will require large-area and dense coatings of yttria-stabilized zirconia (YSZ) while high coating rate is demanded for economic reasons. A combination process of co-evaporation of yttrium and zirconium by EB-PVD from a dual crucible, reactive processing procedure of introducing oxygen, and a spotless arc burning between zirconium as cathode and yttrium as anode were investigated experimentally. The YSZ layers were deposited at relatively high static coating rates (20 to 80 nm s− 1) in comparison to other PVD processes. The cubic crystal structure that was identified by means of XRD corresponds to the YSZ phase with the highest ionic conductivity and is therefore especially well-suited for use as a solid-state electrolyte. Pores were evidenced in the microstructure of the layers deposited at a coating rate of > 50 nm s− 1. Nevertheless, very dense YSZ layers could be obtained at a coating rate of 30 nm s− 1 and a spotless arc current of 300 A. Specific leakage rates of YSZ layers on porous Ni/NiO-YSZ anode substrates measured using air are in the region of 1 Pa m s− 1. The investigations have shown that the intense plasma created with a spotless arc has a considerable influence on growth and microstructure of YSZ layers, even at high coating rates. © 2017 Elsevier B.V.


May C.,Fraunhofer Institute for Electron Beam and Plasma Technology
Optics InfoBase Conference Papers | Year: 2016

Flexible OLED allows new kinds of curved and transparent lighting systems. Specific topics of flexible OLED fabrication by sheet-to-sheet and roll-to-roll processing of polymer webs, metal foils and flexible ultra-thin glass the will be discussed. © OSA 2016.


Fahlteich J.,Fraunhofer Institute for Electron Beam and Plasma Technology | Schonberger W.,Fraunhofer Institute for Electron Beam and Plasma Technology | Fahland M.,Fraunhofer Institute for Electron Beam and Plasma Technology | Schiller N.,Fraunhofer Institute for Electron Beam and Plasma Technology
Surface and Coatings Technology | Year: 2011

Transparent permeation barrier layers are not only used for food packaging but are also needed to encapsulate flexible electronic devices. Magnetron sputtering allows the deposition of high quality oxide barrier layers with a low water vapor and oxygen permeation. This paper compares different metal oxide layers which are deposited onto a polyethylene terephthalate (PET) film using a reactive dual magnetron sputtering process. The oxides of aluminum, silicon, titanium, zinc and a zinc-tin alloy are compared regarding their permeation barrier, structural and surface properties to determine the relationship between the layer structure and the gas permeation. Thereby, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to characterize the morphology and surface structure of the layers and X-ray diffraction analysis (XRD) was used to determine the solid state phase.Cross-section images taken with SEM show a very compact structure for both aluminum oxide and zinc-tin oxide layers. These materials also have the lowest water vapor permeation compared to all other materials. Zinc oxide and titanium oxide layers both exhibit a columnar structure. Zinc oxide is polycrystalline and has a surprising low water vapor and oxygen permeation. In contrast to that the amorphous titanium oxide layers show a high water vapor and oxygen permeation which is not decreasing with an increasing layer thickness above 40. nm. © 2011 Elsevier B.V.


Muhl S.,Fraunhofer Institute for Electron Beam and Plasma Technology | Beyer B.,Fraunhofer Institute for Electron Beam and Plasma Technology
Electronics | Year: 2014

In recent years, both biodegradable and bio-based electronics have attracted increasing interest, but are also controversially discussed at the same time. Yet, it is not clear whether they will contribute to science and technology or whether they will disappear without major impact. The present review will address several aspects while showing the potential opportunities of bio-organic electronics. An overview about the complex terminology of this emerging field is given and test methods are presented which are used to evaluate the biodegradable properties. It will be shown that the majority of components of organic electronics can be substituted by biodegradable or bio-based materials. Moreover, application scenarios are presented where bio-organic materials have advantages compared to conventional ones. A variety of publications are highlighted which encompass typical organic devices like organic light emitting diodes, organic solar cells and organic thin film transistors as well as applications in the field of medicine or agriculture. © 2014 by the authors; licensee MDPI, Basel, Switzerland.


Junghahnel M.,Fraunhofer Institute for Electron Beam and Plasma Technology
Vakuum in Forschung und Praxis | Year: 2014

Flexible glass, such as ultra-slim Corning® Willow® Glass, produced at thicknesses lower than 200 micron has the ability to bend, while maintaining perfect barrier properties, superior surface quality, greater transparency, and high temperature processing, outperforming polymers. At the same time it has the potential to be used in roll-to-roll large area processing. These qualities make flexible glass an outstanding material for displays, touch panels, thin-film batteries and photovoltaic (PV) products. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA.


Fietzke F.,Fraunhofer Institute for Electron Beam and Plasma Technology | Zimmermann B.,Fraunhofer Institute for Electron Beam and Plasma Technology
Surface and Coatings Technology | Year: 2010

An efficient plasma source has been established by arranging a hot hollow cathode electron emitter in a strong axial magnetic field, allowing for a reduction of working gas flow by one order of magnitude without loss of discharge stability. Moreover, with the reduction of gas flow not only an increase of the discharge impedance was observed, but also a multiplication of ion current density together with a highly expanded volume of the plasma plume.By means of spatially resolved Langmuir probe measurements, combined with the usage of an energy-resolved mass-spectrometer, plasma density profiles and energy distribution functions of electrons and ions have been measured. Generally, with an increase of the magnetic field and with the reduction of the working gas flow ion energy distribution functions shift from mean values of a few eV to 10eV and more, while charge carrier densities increase from 109cm-3 to more than 1012cm-3. A strongly increased ability to dissociate and ionize reactive gases was observed.Two promising applications related to the coating of tools and components are discussed: the sputter etching with argon ions and the reactive pulse magnetron sputter deposition of wear-resistant chromium nitride layers. Whereas the first mentioned process provides pre-heating and etching rates higher than all actually used in tool coating industry, the second one offers advantages for film growth kinetics leading to significant improvements in composition, structure, surface morphology, and hardness of the deposited layers. © 2010 Elsevier B.V.


Weller S.,Fraunhofer Institute for Electron Beam and Plasma Technology
Vakuum in Forschung und Praxis | Year: 2015

Ultra-fast thermal annealing of thin films with annealing times of few milliseconds are faster und more energy efficient than conventional furnace annealing methods. By using flash lamp annealing, only the surface is heated while the substrate remains cold. This allows the refinement of indium-tin-oxide films on rigid and ultra-thin flexible glass and improves their conductivity and transmittance. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Zimmermann B.,Fraunhofer Institute for Electron Beam and Plasma Technology | Fietzke F.,Fraunhofer Institute for Electron Beam and Plasma Technology | Moller W.,Helmholtz Center Dresden
Surface and Coatings Technology | Year: 2011

Hollow cathode arc discharges are efficient plasma sources and are applied in substrate pretreatment or plasma-activated deposition processes. In order to generate large volume homogeneous plasmas to guarantee uniformity of plasma activation and coating properties, in the presented configuration a ring-shaped anode is positioned coaxially around the hollow cathode tube. A magnetic field is applied, which is axial within the cathode tube and spreads out in the deposition chamber. In order to characterize the hollow cathode plasma, spatially resolved Langmuir probe measurements have been carried out. The charge carrier density maximum on the cathode tube axis reaches values up to 1013cm-3. With increasing distance from the plasma source, the plasma density decreases and shows a smoother lateral profile. Maxwellian electron energy distribution functions are observed with spatially homogeneous electron temperatures in the range 1-4eV. Increasing the chamber pressure leads to higher plasma densities and lower electron temperatures. Reduction of the gas flow through the hollow cathode tube results in a strong rise of the plasma density over two orders of magnitude. The magnetic field supports the low gas flow mode and leads to higher plasma densities, too. The results of the Langmuir probe measurements are discussed by means of the active zone model and are further related to optical emission measurements performed in the vicinity of the hollow cathode orifice. © 2011 Elsevier B.V.


Vacuum processing enables very precise thin-layer coating of surfaces with many different materials, which can not be used with other surface finishing processes, or they require very high expenditures and are therefore not economical. Almost all metals, as well as many alloys and inorganic compounds can be deposited by so called PVD processes (physical vapour deposition). Plasma-activated electron beam vapour deposition enables the economical manufacturing of high-value coatings at high deposition rates on large surfaces. Four examples of decorative and functional coatings on metal tapes are proving the potential of plasma-activated electron beam vapour deposition.


Beyer B.,Fraunhofer Institute for Electron Beam and Plasma Technology | Leo K.,TU Dresden
Journal of Materials Chemistry C | Year: 2015

Top-absorbing organic solar cells with a light incoupling layer allowing the exposure of harmful UV irradiation have been fabricated. Short-wavelength light is absorbed by the down-shifting system Alq3:DCM located in the light incoupling layer of top-absorbing organic solar cells and is converted into longer wavelengths. This red light is then absorbed by a ZnPc:C60 bulk heterojunction solar cell, showing a total power efficiency increase by more than 10% related to additional photocurrent generated by this architectural concept. © The Royal Society of Chemistry 2015.

Loading Fraunhofer Institute for Electron Beam and Plasma Technology collaborators
Loading Fraunhofer Institute for Electron Beam and Plasma Technology collaborators