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Wissenschaftliche Publikationen

Forschung bedeutet bei Hahn-Schickard auch, die Ergebnisse in wissenschaftlichen Publikationen zu veröffentlichen.

Jahr Name
2020

Review: Library preparation for next generation sequencing: A review of automation strategies

J.F. Hess, T.A. Kohl, M. Kotrová, K. Roensch, T. Paprotka, V. Mohr, T. Hutzenlaub, M. Brüggemann, R. Zengerle, S. Niemann, N. Paust

Biotechnology Advances, 107537, doi: 10.1016/j.biotechadv.2020.107537

2019

Mikrotechnisch hergestelltes 3D-Lorenzkraft-Magnetometer Sensorelement (3DLKM) mit neuartigem multiaxialem Betriebsprinzip und neuartigem Ausleseverfahren

J. Rockstroh, D. Krawat

Abschlussbericht IGF-Vorhaben-Nr.: 18631 N

Kurzfassung einblenden
2020

Improving the water management in anion-exchange membrane fuel cells via ultra-thin, directly deposited solid polymer electrolyte

P. Veh, B. Britton, S. Holdcroft, R. Zengerle, S. Vierrath, M. Breitwieser

RSC Adv 10, 8645 – 8652, doi: 10.1039/C9RA09628K

2020

Inkjet-Printing of Nanoparticle Gold and Silver Ink on Cyclic Olefin Copolymer for DNA-Sensing Applications

M. Trotter, D. Juric, Z. Bagherian, N. Borst, K. Gläser, T. Meissner, F. von Stetten, A. Zimmermann

Sensors 20 (5), 1333, doi: 10.3390/s20051333

2019

An Assessment of Thermoset Injection Molding for Thin-Walled Conformal Encapsulation of Board-Level Electronic Packages

R. Kulkarni, P. Wappler, M. Soltani, M. Haybat, T. Guenther, T. Groezinger, A. Zimmermann

Journal of Manufacturing and Materials Processing (ISSN 2504-4494)

Kurzfassung einblenden

An ever-growing market demand for board (second) level packages (e.g., embedded systems, system-on-a-chip, etc.) poses newer challenges for its manufacturing industry in terms of competitive pricing, higher reliability, and overall dimensions. Such packages are encapsulated for various reasons including thermal management, protection from environmental conditions and dust particles, and enhancing the mechanical stability. In the due course of reducing overall sizes and material saving, an encapsulation as thin as possible imposes its own significance. Such a thin-walled conformal encapsulation serves as an added advantage by reducing the thermo-mechanical stresses occurring due to thermal-cyclic loading, compared to block-sized or thicker encapsulations. This paper assesses the encapsulation process of a board-level package by means of thermoset injection molding. Various aspects reviewed in this paper include the conception of a demonstrator, investigation of the flow simulation of the injection molding process, execution of molding trials with different encapsulation thicknesses, and characterization of the packages. The process shows a high dependence on the substrate properties, injection molding process parameters, device mounting tolerances, and device geometry tolerances. Nevertheless, the thermoset injection molding process is suitable for the encapsulation of board-level packages limiting itself only with respect to the thickness of the encapsulation material, which depends on other external aforementioned factors.


Link zum Paper

2019

A Novel Approach for Reliability Investigation of LEDs on Molded Interconnect Devices Based on FE-Analysis Coupled to Injection Molding Simulation

M. Soltani, R. Kulkarni ,T. Scheinost, T. Groezinger, A. Zimmermann

IEEE Access, DOI: 10.1109/ACCESS.2019.2913786, Bd. 7, pp. 56163–56173

2019

A Novel Approach for Lifetime Estimation of Electronic Components mounted on Plastic Substrates by Coupling Injection Molding Simulation to FE-Analysis

M. Soltani, R. Kulkarni ,T. Groezinger, A. Zimmermann

International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES), 16.06.2019 - 20.06.2019, Wilmington, USA

2019

Zuverlässigkeitsuntersuchungen und Lebensdauermodelle von LEDs auf räumlichen Schaltungsträgern

M. Soltani

Workshop Visions to Products MID and Beyond, 15.10.2019, Stuttgart, Deutschland

2019

Quadrature Block for UHF Reflection Coefficient Measurements Using a Directional Coupler and Injection Locking

André Bülau

IEEE Transactions on Instrumentation and Measurement, DOI: 10.1109/TIM.2019.2895480

2020

Review: Electrochemical DNA sensing – Principles, commercial systems, and applications

M. Trotter, N. Borst, R. Thewes, F. von Stetten

Biosensors & Bioelectronics 154, 112069, doi: 10.1016/j.bios.2020.112069

2019

Miniaturized Optical Encoder with Micro Structured Encoder Disc

A. Bülau

Appl. Sci. 2019, 9(3), 452, DOI: 10.3390/app9030452

Kurzfassung einblenden

A novel optical incremental and absolute encoder based on an optical application-specific integrated circuit (opto-ASIC) and an encoder disc carrying micro manufactured structures is presented. The physical basis of the encoder is the diffraction of light using a reflective phase grating. The opto-ASIC contains a ring of photodiodes that represents the encryption of the encoder. It also includes the analog signal conditioning, the signal acquisition, and the control of a light source, as well as the digital position processing. The development and fabrication of the opto-ASIC is also described in this work. A laser diode was assembled in the center on top of the opto-ASIC, together with a micro manufactured polymer lens. The latter was fabricated using ultra-precision machining. The encoder disc was fabricated using micro injection molding and contains micro structures forming a blazed grating. This way, a 10-bit optical encoder with a form factor of only 1 cm3 was realized and tested successfully.


Link zum Paper

2019

Inertialsensorik und Neigungswinkelsensorik

A. Schwenck

3. VDI-Fachkonferenz Sensoren für mobile Maschinen, 04.12.2019 – 05.12.2019, Ulm, Deutschland

Kurzfassung einblenden
  • Überblick, Stand der Technik
  • Beschleunigungssensoren in Silizium Mikromechanik zur Bestimmung
    der Lage im Raum
  • Kapazitiver, fluidischer Neigungssensor zur Bestimmung der Lage
    im Raum
  • Anwendungsbeispiele
2019

Void formation in solder joints under power cycling conditions and its effect on reliability

J. Mei, R. Haug, S. Hinderberger, T. Grözinger, A. Zimmermann

Microelectronics Reliability, Volumes 100–101: 113350

Kurzfassung einblenden

When electronic assemblies are experiencing high current loading conditions, thermo-mechanical mismatch induced from the local Joule heating of the component and electromigration (EM)-induced void formation can lead to the failure of the solder interconnect. Scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) are adopted to investigate the microstructural evolution of solder joints of shunt components subjected to current stressing. Voids and micro-cracks initiate at the corner of solder meniscus, where the maximal divergence of material flux density is located on the basis of finite element method (FEM) simulation. The EM-induced voids introduce higher accumulated plastic strain in the solder joints, which will result in reduction in the lifetime of the electronic assemblies.


Link zum Paper

2019

Optimized Micro-Mounting and Hybrid Integration of RF Mixed-Signal Systems based on MID Technology, Smart Systems Integration

M. Wolf, M. Barth, W. Eberhardt, A. Zimmermann, V. Geneiß, C. Hedayat, T. Otto

Barcelona, VDE Verlag GmbH, 10.-11.4.2019, pp. 383 - 386

2019

Miniaturized Optical Encoder with Micro Structured Encoder Disc

J. Seybold, A. Bülau, K.-P. Fritz, A. Frank, C. Scherjon, J. Burghartz, A. Zimmermann

Micro/Nano Manufacturing, Applied Sciences (ISSN 2076-3417), pp. 104 - 118

2019

Räumliche Elektronik auf Basis von räumlichen Schaltungsträgern

H. Müller, W. Eberhardt, F. Kern

Plus 5/2019, pp. 758-760

2019

An UHF Software Defined Reflectometer using Under-Sampling Down-Conversion in the ADC

V. Kible, R. Nunes de Lima, K. Brito de Brito, A. Bülau, A. Zimmermann

European Microwave Week 2019 (EUMW/EUMC), 29.09.2019 – 04.10.2019, präsentiert 2.10.2019, Paris, Frankreich
Gefördert von brasilianischen Institutionen: CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) und FAPESB (Fundação de Amparo à Pesquisa do Estado da Bahia).

Kurzfassung einblenden

Radio frequency reflectometry is widely used in non-destructive characterization of various materials and can also be applied to automatic impedance matching systems in telecommunication devices. Here, a novel, low cost, software defined approach for measuring the reflection coefficient without using mixers or power detectors is proposed, enabled by using under-sampling down-conversion with an analog-digital-converter. Minimizing the analog part of the system removes possible error sources and a modular design allows application in different fields as well as an implementation as an integrated circuit. Computer simulations as well as measurement results on a printed circuit board setup for a system frequency of 400 MHz are presented, permitting extrapolation to other ultra-high frequencies.


Link zum Paper

2019

Challenges in the Fabrication of Microstructured Polymer Optics

M. Roeder, P. Schilling, K.-P. Fritz, T. Guenther, A. Zimmermann

Journal of Micro- and Nano-Manufacturing; JUNE 2019, Vol. 7 / 021001-1, [DOI: 10.1115/1.4044219], pp. 1-6, Project AiF-RP-No. 18556 N und Project InnBW IDAK

Kurzfassung einblenden

The fabrication of microstructured polymer optics enables a multitude of new options in the design of technical optics. However, challenges arise along the varying process chains of mold insert fabrication, integration into molding tools, replication by means of injection compression molding and metrology. In order to study the effects, diffractive optical elements (DOE) and microlens arrays (MLA) are fabricated using two different process chains. DOEs are fabricated using a laser direct writing (LDW) based mold insert fabrication. The MLA mold insert is produced using ultra-precision milling (UPmilling). Both optical parts are replicated using injection compression molding. The occurring effects are discussed and the results show, that with complete process control high quality microstructured polymer optical parts can be produced and characterized.


Link zum Paper

2019

Fabrication of curved diffractive optical elements by means of laser direct writing, electroplating, and injection compression molding

M. Roeder, S. Thiele, D. Hera, C. Pruss, T. Guenther, W. Osten, A. Zimmermann

Journal of Manufacturing ProcessesVolume 47, November 2019, pp. 402-409, Project AiF-RP-No. 18556 N

Kurzfassung einblenden

In this work, a new process chain for the fabrication of curved micro-structured optical elements by injection compression molding is investigated. The fabrication is demonstrated for the example of a curved diffractive optical element (DOE). In a first process step a master substrate is fabricated using laser direct writing on a curved glass substrate. Blazed diffractive micro-structures with lateral feature sizes down to 5 μm and height of 1.6 μm are created. A subsequent electroplating process is applied to create a nickel stamper to be used as a tool insert for the molding process. During electroplating, a 3 mm nickel layer is formed, transferring the diffractive structures from the master substrate into a solid mold insert. The nickel stamper shows an accurate reproduction of the micro-structures. The mold insert is integrated into an injection compression molding tool to replicate the optical elements. Results show that the blazed diffractive structures are replicated with a high quality. Tests of the components within a chromatic-confocal measurement setup confirm that they can potentially replace expensive conventional elements.


Link zum Paper

2019

Review on Fabrication Technologies for OpticalMold Inserts

M. Roeder, T. Guenther, A. Zimmermann

Micromachines 2019, 10, 233; doi:10.3390/mi10040233, pp. 1-25, Project AiF-RP-No. 18556 N und Project InnBW IDAK

Kurzfassung einblenden

Polymer optics have gained increasing importance in recent years. With advancing requirements for the optical components, the fabrication process remains a challenge. In particular, the fabrication of the mold inserts for the replication process is crucial for obtaining high-quality optical components. This review focuses on fabrication technologies for optical mold inserts. Thereby, two main types of technologies can be distinguished: fabrication methods to create mold inserts with optical surface quality and methods to create optical microstructures. Since optical mold inserts usually require outstanding form accuracies and surface qualities, a focus is placed on these factors. This review aims to give an overview of available methods as well as support the selection process when a fabrication technology is needed for a defined application. Furthermore, references are given to detailed descriptions of each technology if a deeper understanding of the processes is required.


Link zum Paper