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    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Zeitschriftenartikel

    Werner Bogner, Johannes Jakob, R. Weigel, Franz Xaver Röhrl, Stefan Zorn

    Bare die connections via aerosol jet technology for millimeter wave applications

    International Journal of Microwave and Wireless Technologies, vol. 11, no. Special Issue 5-6 (EuMW 2018 Special Issue (Part I)) [June], pp. 441-446

    2019

    DOI: 10.1017/S1759078719000114

    Abstract anzeigen

    This paper presents a comparison of chip connections using aerosol jet (AJ) and bond technology on low-cost printed circuit board (PCB) substrates. First, the behavior of the used gap filler material and the used silver ink for AJ technology on PCBs are characterized. In addition to comparing the radio frequency (RF) performance (DC to 67 GHz) of the two technologies, the mechanical stability is also compared. While the AJ technology transitions score above all for their RF performance and the lower requirements (surface finish, pad size, and adhesion) on the PCB, the bonding technology has clear advantages, especially with a different coefficient of thermal expansion values of the substrates to be connected. Finally, the measurement results of a complete package are shown, whereby the chip connection is realized once by means of AJ and once by bonding wires.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Werner Bogner, Franz Xaver Röhrl, Felix Sepaintner, Stefan Zorn, Andreas Scharl

    Simulation and Manufacturing of Low Loss PCB Structures with Additional Electromagnetic Field in Air

    Proceedings of the IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes (IMWS-AMP) [July 16-18, 2019; Bochum]

    2019

    DigitalNachhaltigElektrotechnik und MedientechnikInstitut ProtectIT

    Beitrag (Sammelband oder Tagungsband)

    Martin Schramm, D. Fiala, Laurin Dörr, Michael Heigl

    On the Energy Consumption of Quantum-resistant Cryptographic Software Implementations Suitable for Wireless Sensor Networks

    Proceedings of the 16th International Joint Conference on e-Business and Telecommunications (July 26-28, 2019; Prague, Czech Republic), vol. Vol. 2 (SECRYPT 2019 : 16th International Conference on Security and Cryptography)

    2019

    DOI: 10.5220/0007835600720083

    Abstract anzeigen

    For an effective protection of the communication in Wireless Sensor Networks (WSN) facing e.g. threats by quantum computers in the near future, it is necessary to examine the applicability of quantum-resistant mechanisms in this field. It is the aim of this article to survey possible candidate schemes utilizable on sensor nodes and to compare the energy consumption of a selection of freely-available software implementations using a WSN-ready Texas Instruments CC1350 LaunchPad ARM® Cortex®-M3 microcontroller board.

    DigitalNachhaltigElektrotechnik und MedientechnikInstitut ProtectIT

    Beitrag (Sammelband oder Tagungsband)

    Martin Schramm, D. Fiala, Laurin Dörr, Michael Heigl

    Comparison of Energy-Efficient Key Management Protocols for Wireless Sensor Networks

    Proceedings of the 2019 International Electronics Communication Conference (IECC '19) [July 7-9, 2019; Okinawa, Japan]

    2019

    DOI: 10.1145/3343147.3343156

    Abstract anzeigen

    A Wireless Sensor Network (WSN) contains small sensor nodes which monitor physical or environmental conditions. WSN is an important technology for digitalization of industrial periphery and is often used in environments which are not hardened against security impacts. These networks are easy to attack due to the open communication medium and low computing resources of the applied devices. Establishing security mechanisms is difficult while taking into account low energy consumption. Low cost sensors with limited resources make the implementation of cryptographic algorithms even more challenging. For WSNs cryptographic functions are needed without high impact on energy consumption and latency. Therefore, security in WSNs is a challenging field of research. This paper compares lightweight energy-efficient key exchange protocols which are suitable for WSN. The protocols were also implemented in WSN-capable Texas Instrument boards and the energy consumption was measured during the key exchange. This paper shows that schemes have to be chosen depending on the specific network requirements and that the usage of asymmetric cryptography does not always result in a high energy consumption.

    NachhaltigElektrotechnik und MedientechnikTC Freyung

    Beitrag (Sammelband oder Tagungsband)

    Melanie Piser, Roland Zink, Sebastian Wöllmann

    Smart Landscapes and PUBinPLAN - Digital Participation for Creating Sustainable Rural Regions

    Proceedings of the 9th International Conference on Advanced Computer Information Technologies (ACIT) [June 5-7, 2019; České Budějovice, Czech Republic]

    2019

    DOI: 10.1109/ACITT.2019.8779892

    Abstract anzeigen

    This paper discusses the impact of ICT for creating sustainable rural regions. An empirical analysis of 255 Bavarian communes in 2018 showed, that there is a lack of digital content on the communes' homepages. New ideas are needed for participation and communication in rural communes. To close this gap, PUB in PLAN, a digital participation platform was initiated. This platform is the basement for new, smart and effective participation projects using digital and analog forms of moderation for sustainable and intelligent city developments.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Beitrag (Sammelband oder Tagungsband)

    Günther Ruhl, T. Ullrich, Benedikt Winter, Raimund Förg, Alois Kasberger

    Entwicklung einer wasserdichten LED Flächenleuchte mit direkt im Glas eingebrachtem Konvertermaterial

    Poster

    DGaO Proceedings zur 120. Jahrestagung (11.-15.06.2019; Darmstadt)

    2019

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Patent

    Günther Ruhl, M. König

    Schichtstruktur und Verfahren zur Herstellung einer Schichtstruktur

    2019

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    M. Pohl, R. Boerret, Rolf Rascher, U. Bielke, Olga Kukso

    MSF-error prevention strategies for the grinding process

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2526581

    Abstract anzeigen

    This research is focused on the link between manufacturing parameters and the resulting mid-spatial frequency error in the manufacturing process of precision optics. This third publication focuses on strategies of avoidance and generation mechanisms of the mid-spatial frequency errors from the grinding process. The Goal is to understand the generation mechanisms of the mid-spatial frequency errors and avoid their appearance in the manufacturing process.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Gerald Fütterer, Simon Wittl, Lucas Bauer, Michael Wagner

    Alignment and thermal drift aspects of a four-tilted-mirror student project telescope

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2530076

    Abstract anzeigen

    The Deggendorf Institute of Technology (DIT) and its Faculty of Applied Natural Sciences and Industrial engineering transfer a broad spectrum of knowledge to the students. The clarification of the interrelations that exist between seemingly isolated fields of knowledge is a permanent process. In order to put this into practice, a telescope construction project was started. The base of the in-house student project is the Technology Campus in Teisnach, which bundles capacities for process development, production and measurement of high-precision optics, including telescope optics. A first optical design, which is based on a subset of the parameter space published in 1989 by M. Brunn1, 2 (later built by D. Stevick as f/12-system3 ), made use of a primary mirror M1 with a diameter of 400 mm. An f/8-system provide a Strehl ratio SR ≥ 0.8 over an entire field of view of 0.7° deg. Even if this seems to be sufficient, manufacturing tolerances, adjustment tolerances, thermal drift and positional changes considerably reduce the Strehl ratio. In order to obtain reliable values of acceptable tolerances, statistical Monte Carlo analyses had been carried out. As consequences, the tube design was changed and the design of new mirror mounts started. This was done to achieve the required stiffness. The new tube designs, one based on carbon-fiber-reinforced polymer (CFRP) and one based on FeNi36, had been tested by using FEM analysis. In addition, the practicability of deep learning based aberration detection was tested. Zernike polynomials obtained by analyzing the star images with a Convolutional Neuronal Network (CNN). The current state of the development is described.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Gerald Fütterer

    Wave front sensing for metrology by using optical filter

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2530013

    Abstract anzeigen

    An interferometric problem is the limited fringe density, which is due to the limited allowed slope difference of superimposed wave fronts. Thus, the angular dynamic range of measurable surfaces and objects under test is limited. In other words, all shapes that deviate from a plane surface or a sphere represent a measuring problem in interferometers, or require an individually adapted null optics, which might cost e.g. 10 k∈ or more. In addition, ground surfaces cannot be measured in standard interferometers, except by using Speckle interferometry, which is limited in resolution. Freeform optics are very problematic. Even when polished, only tactile or confocal coordinate measurement might work. Several interferometers address the problem of the angular deviation to a sphere. For instance, lateral stitching on a curved surface, which is equivalent to the best-fit sphere, or longitudinal stitching is used. To use a tilted wave interferometer for asphere metrology is another option, which provides versatile measurement configurations. The approach discussed here is to use optical filters. The development of this technique is part of a project most recently started at the Technology Campus in Teisnach. The surface under test (SUT) is imaged onto an optical filter, which has a calibrated angular selectivity. Thus, the angles of the local wave front normal vectors are transferred into an intensity distribution. A set of angular measurements enables reduced uncertainty of the wave front measurement. Aspects as e.g. the working principle, boundary conditions and the identification of practical filters are discussed in the paper.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Jakob Reitberger, Rolf Rascher, Johannes Liebl, Sebastian Sitzberger

    Zero-point clamping systems in optical production

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2528774

    Abstract anzeigen

    Zero point clamping systems are an integral part of the manufacturing industry. They have only yet to find their way into the optical industry. This article compares the hydraulic expansion holder, a clamping system currently used in the optical industry with a zero-point clamping system. The achievable accuracies of both systems are compared over several measurement series. In addition, the process capability evaluation is used for the comparison. Finally, the results are summarized to provide every researcher and practitioner with a foundation for assessing whether zero point clamping systems meet the requirements for the use in optical manufacturing.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Christine Wünsche, S. Höfer, Jessica Stelzl

    Processing of a new nonlinear optical crystal for continuous wave UV-laser applications

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2528140

    Abstract anzeigen

    Lasers have been known for a long time and are used in a wide variety of fields such as industrial and material processing or measuring and control technology. A new application is being tested which aims to use continuous wave UV-lasers in metrology. For this application a nonlinear optical crystal is needed. Its processing is developed in a two-year project at the Institute for Precision Manufacturing and High-Frequency Technology of Deggendorf Institute of Technology. The crucial factor for the full optical performance in the UV range is the low roughness of the crystal surface, as it is installed between two prisms and the contactability between them should be ensured. In China, a nonlinear crystal that meets the requirements has already been designed and a production process for the raw crystal has been established. However, since the production of optically homogenous crystals has proven to be difficult, the availability of such is very limited. For this reason, a reference material with similar hardness and material behaviour is used in the process development in order not to be limited in the number of trials. It is important to be able to transfer the results from the reference material in an analogous way to the original crystal. One challenge of the project lies in the crystal thickness, since only a maximum thickness of three millimetres can be achieved for the purest form of the crystal required in the application. Therefore, it is important to handle the material sparingly during the process. In addition, the small dimensions of about ten to five millimetres and the brittleness of the material pose a problem. The goal of the project will be to develop a process that can circumvent all these problems so that small roughness of the crystal can be achieved by precision polishing.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Christine Wünsche, S. Herr, S. Mechold, Emilio Zambrano

    Cleaning effects in optical layers: error characteristics and analysis methods

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2527974

    Abstract anzeigen

    In the course of the ever-increasing demand of high-performance optical components, dielectric coating processes are the key technology for the refinement of optics, ensuring their functionality. These optics are based on optical interference coatings, which are formed by a layer stack of alternating transparent single layers of high and low refractive index material. Assuming that turbidity as well as defects embedded in coatings are considered as a primary factor limiting the quality of optical coatings, the level of cleaning the substrates before coating has to be extremely high. Particular importance is attached to the interface between the layer stack and the substrate, especially to the interaction during the transition from the glass surface to the coating during the manufacturing process. This interaction is assumed to be caused by polishing, by corrosion during storage time or by effects during cleaning of the substrate before coating. Thus, it is necessary to characterize each type of defect and to define which technique is adequate to analyze each one of them efficiently. The project aims to raise the awareness and knowledge in terms of what happens during the coating process and, in particular, to understand the physical processes at the substrate during the manufacturing process. After analyzing the material flow, first focus was set on the cleaning procedure. It is assumed that one of the main influences on defects in the interface is the chemical cleaning. Chemical reactions on the surface of the glass substrate may occur due to additional effects of external components and elevated temperature in the washing basins.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Rolf Rascher, Johannes Liebl, S. Killinger

    Mid-spatial frequency errors in feed direction occurring in ADAPT polishing

    Proceedings of SPIE 11171 (Sixth European Seminar on Precision Optics Manufacturing, 1117101 [April 9th-10th 2019, Teisnach]), Bellingham, WA, USA

    2019

    DOI: 10.1117/12.2528114

    Abstract anzeigen

    Previous work shows the effectiveness of computer controlled polishing (CCP) with the ADAPT tool by Satisloh for correcting form errors in optics manufacturing. This method however has a risk of producing residual errors in the range of mid spatial frequency errors (MSFE). In order to prevent these errors the residual in feed direction is investigated as well as the behavior at different parameters.

    DigitalNachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenIPH Teisnach

    Beitrag (Sammelband oder Tagungsband)

    Werner Bogner, Johannes Jakob, R. Sammer, Franz Xaver Röhrl, Stefan Zorn

    WR12 to planar transmission line transition on organic substrate

    Proceedings of the 49th European Microwave Conference (EuMC)/European Microwave Week (EuMW) 2019 (September 29-October 4, 2019; Paris, France)

    2019

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Zeitschriftenartikel

    J.-M. Batke, S. Wittman, Günther Ruhl, I. Costina, M. Lemme, T. Preis, M. König, A. Gahoi

    Accurate Graphene-Metal Junction Characterization

    IEEE Journal of the Electron Devices Society (J-EDS), vol. 7, pp. 219-226

    2019

    DOI: 10.1109/JEDS.2019.2891516

    Abstract anzeigen

    A reliable method is proposed for measuring specific contact resistivity (p C ) for graphenemetal contacts, which is based on a contact end resistance measurement. We investigate the proposed method with simulations and confirm that the sheet resistance under the metal contact (R SK ) plays an important role, as it influences the potential barrier at the graphene-metal junction. Two different complementary metal-oxide-semiconductor-compatible aluminum-based contacts are investigated to demonstrate the importance of the sheet resistance under the metal contact: the difference in R SK arises from the formation of insulating aluminum oxide (Al 2 O 3 ) and aluminum carbide (Al 4 C 3 ) interfacial layers, which depends on the graphene pretreatment and process conditions. Auger electron spectroscopy and X-ray photoelectron spectroscopy support electrical data. The method allows direct measurements of contact parameters with one contact pair and enables small test structures. It is further more reliable than the conventional transfer length method when the sheet resistance of the material under the contact is large. The proposed method is thus ideal for geometrically small contacts where it minimizes measurement errors and it can be applied in particular to study emerging devices and materials.

    NachhaltigAngewandte Naturwissenschaften und Wirtschaftsingenieurwesen

    Zeitschriftenartikel

    Hongyu Zhang, Jizhong Sun, Ali Hamid, Thomas Stirner, Arvind Jadon

    Molecular dynamics simulations of helium clustering and bubble growth under tungsten surfaces

    Computational Materials Science, vol. 163, no. June, pp. 141-147

    2019

    DOI: 10.1016/j.commatsci.2019.03.008

    Abstract anzeigen

    We study the surface response of W to helium bombardment using molecular dynamics simulations. Simulations have been performed for incident helium of energy 80 eV and surface temperature 2100 K. The saturation of He retention has been observed to be high, a result of the bubbles trapping helium atoms and preventing them from diffusing to the surface and further back into the plasma. On the other hand, we have observe near-surface “cluster rupture” leading to the expulsion of helium atoms towards the vacuum. We have found that bubbles typically grow in a relatively narrow band of He/V ratios (1–3). Besides, it was observed that tungsten atoms migrated from the top surface into the bulk. The coalescence of helium bubbles has also been observed.

    NachhaltigAngewandte Naturwissenschaften und Wirtschaftsingenieurwesen

    Zeitschriftenartikel

    Thomas Stirner, David Scholz

    Convergence of surface energy calculations for various methods: (0 0 1) hematite as benchmark

    Journal of Physics: Condensed Matter, vol. 31, no. 19

    2019

    DOI: 10.1088/1361-648X/ab069d

    Abstract anzeigen

    Different methods for calculating the surface energy from ab initio simulations are applied to the relaxed (0 0 1) surface of the metal oxide hematite ([Formula: see text]-Fe2O3). The simulations are carried out with a rather moderate k-point grid with shrinking factors of (6 6 6) for all bulk and (6 6) for all slab simulations. Very good convergence is obtained if a linear fit of the slab energies with respect to the number of layers in the slab is performed. In comparison to the other methods employed, this procedure is ultimately the most accurate and reliable method for extracting convergent surface energies from (0 0 1) hematite slabs. Additionally, we propose a way to determine the least possible starting point for calculating the surface energy by the linear-fit method. Furthermore, we find the Boettger method to perform nearly equally well, if the bulk energy is extracted from the energy difference per layer between the slabs with 12 and 18 layers thickness. Both methods give a surface energy of 2.43 J m-2 with a deviation of less than [Formula: see text]0.005 J m-2. The standard approach, which uses a separate bulk simulation, instead shows a significant linear divergence with increasing number of layers in the slab. We also carried out bulk simulations with a surface-oriented bulk unit cell, but found it in our case not to improve the convergence of the standard approach.

    NachhaltigAngewandte Naturwissenschaften und WirtschaftsingenieurwesenTAZ Spiegelau

    Patent

    G. Poeppel, Günther Ruhl, T. Hirsch, H. Roedig

    Sensor arrangement for particle analysis and a method for particle analysis

    2019