TY - JOUR A1 - Schreck, Timo A1 - Schnorpfeil, Anna A1 - Kaloudis, Michael T1 - Analysing the growth of intermetallic compounds in lead-free solder joints by differential scanning calorimetry measurements JF - Journal of Materials Science KW - intermetallic compounds KW - Differential scanning calorimetry KW - Lötverbindung Y1 - 2013 U6 - https://doi.org/10.1007/s10853-012-7035-5 VL - 48(2013) IS - 6 SP - 2476 EP - 2484 ER - TY - JOUR A1 - Rauer, Miriam A1 - Kaloudis, Michael T1 - Ausfallanalyse an einem Lithium-Ionen Akkumulator JF - Maschinenmarkt KW - Lithium-Ionen-Akkumulator Y1 - 2014 VL - 2014 IS - 2 SP - 45 EP - 46 ER - TY - JOUR A1 - Heininger, Patrick A1 - Schreck, Timo A1 - Kaloudis, Michael T1 - Buckelschweißen zur zuverlässigen Kontaktierung von Industrieakkumulatoren JF - PLUS 14 KW - Buckelschweißen KW - Buckelschweißen KW - Akkumulator Y1 - 2012 IS - 5 SP - 1163 EP - 1169 ER - TY - CHAP A1 - Stenzel, David A1 - Schwarzer, Christian A1 - Schnepf, Michael A1 - Schmitt, Wolfgang A1 - Blank, Thomas A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - Characterization of Alternative Sinter Materials for Power Electronics T2 - 22nd Microelectronics and Packaging Conference (EMPC) & Exhibition, 16 Sep 2019 - 19 Sep 2019, Conference Center PISA, Italy KW - Sintern, Silber, Kupfer KW - Leistungselektronik KW - Sintern Y1 - 2019 ER - TY - JOUR A1 - Rauer, Miriam A1 - Volkert, Antje A1 - Härter, Stefan A1 - Schreck, Timo A1 - Kaloudis, Michael ED - Stevenson, Michael T1 - Computed-Tomography-Based Analysis of Voids in SnBi57Ag1 Solder Joints and Their Influence on the Reliability JF - Journal of Failure Analysis and Prevention KW - Computertomographie KW - Löten Y1 - 2014 VL - 14 IS - 3 SP - 272 EP - 281 ER - TY - JOUR A1 - Rauer, Miriam A1 - Kaloudis, Michael T1 - Computertomographie erweitert das Blickfeld JF - Mikroproduktion KW - Computertomographie Y1 - 2014 VL - 2014 IS - 1 SP - 50 EP - 51 ER - TY - CHAP A1 - Kaloumenos, Mareiki A1 - Amrhein, Frank A1 - Glaab, Johannes A1 - Sauer, Michael A1 - Hellmann, Ralf A1 - Kaloudis, Michael T1 - Development of a UV-Light Source with Highest Power Density Based on Light Emitting Diode Technology for Applications in Production Engineering, in Production Engineering and manufacturing Systems T2 - Proceedings of the XXIV International Scientific Conference Miskolc, Ungarn KW - Lumineszenzdiode Y1 - 2010 ER - TY - JOUR A1 - Braunwarth, Louisa A1 - Amrhein, Sebastian A1 - Schreck, Timo A1 - Kaloudis, Michael ED - Huisingh, Donald T1 - Ecological comparison of soldering and sintering as die-attach technologies in power electronics JF - Journal of Cleaner Production N2 - In this study the method of life cycle assessment is used to perform a comparison of two die-attach technologies of power modules: silver sintering and common soldering with a tin–silver–copper solder. The goal of the study is to indicate which die-attach technique is more environmentally friendly. This is important in order to design future electronics more environmentally friendly. Processing covers the manufacturing of the respective pastes, application of pastes, and mounting as well as the subsequent sintering or soldering, including cleaning of the soldered parts. The last step in the processing is a wire bonding process. The environmental impacts are expressed in CO2-equivalents and ReCiPe points and different variants are discussed: comparisons are made between considered pastes and between a soldered and a sintered power module, including consideration of lifetime. Concerning sintering, the influence of using recycled silver is analyzed more closely. The types of stages included in this life cycle assessment best fit a cradle-to-gate assessment, because usage, recycling, and disposal are not included. The software used is OpenLCA version 1.3.3, created by GreenDelta, and the database used is Ecoinvent version 2.2. In order to fill data gaps, electronics manufacturing companies were contacted, and our own calculations and measurements were applied. The consideration of the wet film thicknesses of the soldering system and sintering system, respectively, results in very similar CO2-equivalent emissions for sinter paste and solder paste. Comparing the soldered power module to the sintered one shows minor to significant differences between the two systems which could easily be changed when changing circumstances and assumptions. But when considering the respective lifetimes of the joining technologies, sintering technology is clearly preferable to the conventional soldering technology. Using solely recycled silver for manufacturing of silver sinter paste reduces the CO2-equivalent emissions of one sintered power module by roughly 40%. The results clearly show the dependence of outcomes on the initial settings. Consideration of lifetime has an enormous impact on the comparison of soldering technology to sintering technology. But the benefit of this life extension through the use of sintering technology is only useful when a long lifetime is required. KW - Life cycle assessment; Solder; Sinter; Die-attach; Power electronics; Environment KW - Löten KW - Sintern KW - Leistungselektronik Y1 - 2015 VL - 23 IS - 102 SP - 408 EP - 417 ER - TY - JOUR A1 - Schneider, Johannes A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael A1 - Gockel, Tilo T1 - Effiziente Entwärmung eines Hochleistungs-UV-LED-Moduls JF - Elektor, Sonderheft LEDs 3 KW - Lumineszenzdiode Y1 - 2011 VL - 2011 IS - 9 SP - 12 EP - 17 ER - TY - JOUR A1 - Amrhein, Sebastian A1 - Schneider, Mareike A1 - Kaloudis, Michael T1 - Ein zweites Leben für den Akku JF - ReSource KW - Lithium-Ionen-Akkumulator KW - Elektrofahrrad Y1 - 2016 VL - 2016 IS - 1 SP - 10 EP - 16 ER - TY - CHAP A1 - Rauer, Miriam A1 - Xu, Ping A1 - Reinhardt, Andreas A1 - Kaloudis, Michael A1 - Franke, Jörg T1 - Einfluss von Poren in Lötverbindungen bei LED-Anwendungen T2 - Elektronische Baugruppen und Leiterplatten – EBL 2016 KW - Lötverbindung KW - Lumineszenzdiode KW - Pore Y1 - 2016 SN - 978-3-8007-4147-2 SP - 135 EP - 139 PB - VDE Verlag CY - Berlin ER - TY - JOUR A1 - Sahl, Martin A1 - Kaloudis, Michael T1 - Einsatz von Glasloten zur Erzeugung gasdichter Fügestellen beim Aufbau von Drucksensoren JF - PLUS KW - Drucksensor KW - Glaslot Y1 - 2010 IS - 12 SP - 1367 PB - Leuze-Verlag CY - Bad Saulgau ER - TY - JOUR A1 - Rauer, Miriam A1 - Kaloudis, Michael T1 - Hinter der Fassade - Ausfallanalyse an einem Lithium-Ionen Akkumulator mittels CT JF - QZ Qualität und Zuverlässigkeit KW - Ausfallanalyse KW - Lithium-Ionen-Akkumulator KW - Ausfallanalyse Y1 - 2013 VL - 2013 IS - 1 SP - 40 EP - 41 ER - TY - CHAP A1 - Sauer, Theresia A1 - Kefer, Stefan A1 - Ruppert, Wolfgang A1 - Hellmann, Ralf A1 - Kaloudis, Michael T1 - Integration of Bragg grating sensors in components made of carbon fiber reinforced polymers T2 - Tagungsband der 20. GMA/ITG-Fachtagung Sensoren und Messsysteme 2019, 25.06.2019 - 26.06.2019, Nürnberg, Deutschland N2 - This contribution discusses the integration of polymer planar Bragg grating sensors (PPBG) into carbon fiber reinforced polymer (CFRP) components. For the first time, it is shown that PPBGs based on cyclic olefin copolymers can be integrated into commercial-grade composites, thereby withstanding the demanding production processes. Pre-impregnated fibers are stacked and partially modified to form a sensor pocket. Afterwards, the CFRP specimen containing the optical sensor is cured in a heated mechanical press for 2 hours at a pressure of 7 bar and a temperature of 120 °C. A subsequent evalutaion of the sensor signal shows a Bragg wavelength shift of 1236 pm and a decline in signal amplitude of -2 dB. Three-point flexural tests of the cured sample reveal a linear behavior of the sensor signal towards external loads. The determined sensitivity in dependence of the CFRP specimen's maximum central deflection is -112 pm/mm, while correlation to the applied force results in a sensitivity of -5 pm/N. KW - Bragg grating sensors KW - carbon fiber reinforced polymers KW - cyclic olefin copolymers KW - structural health monitoring KW - Bragg-Reflektor Y1 - 2019 SN - 978-3-9819376-0-2 U6 - https://doi.org/10.5162/sensoren2019/P3.12 SP - 806 EP - 810 ER - TY - JOUR A1 - Bachmann, Marco A1 - Amrhein, Sebastian A1 - Kaloudis, Michael T1 - Intelligente Pedelecs fördern. Ein Ansatz zur nachhaltigen Verbesserung unseres Mobilitätsverhaltens JF - Internationales Verkehrswesen KW - Pedelec Y1 - 2016 VL - 2016 IS - 1 SP - 16 EP - 19 ER - TY - JOUR A1 - Fuchs, Christopher A1 - Schreck, Timo A1 - Kaloudis, Michael T1 - Interfacial reactions between Sn 57Bi 1Ag solder and electroless Ni-P/immersion Au under solid-state aging JF - Journal of Materials Science KW - interfacial reactions KW - Intermetallische Verbindungen Y1 - 2014 VL - 47 IS - 9 SP - 4036 EP - 4041 ER - TY - CHAP A1 - Schmitt, Wolfgang A1 - Schnepf, Michael A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - Investigation of a Sintering Process for Micro-Scale Copper Material T2 - 2019 SMTA Electronic in Harsh Environments Conference KW - Kupfer KW - Sintern Y1 - 2019 VL - 2019 ER - TY - CHAP A1 - Schwarzer, Christian A1 - Chew, Ly May A1 - Schnepf, Michael A1 - Stoll, Thomas A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - INVESTIGATION OF COPPER SINTER MATERIAL FOR DIE ATTACH T2 - SMTA International Conference Proceedings KW - Leistungshalbleiter KW - Leistungselektronik KW - Kupfer KW - Sintern Y1 - 2018 VL - 2018 IS - Proceedings SMTAI 2018 CY - Rosemont ER - TY - CHAP A1 - Hensel, Alexander A1 - Roth, Frederick A1 - Merz, Corinna A1 - Franke, Jörg A1 - Kaloudis, Michael T1 - Investigation of Pressureless Sintered Interconnections on Plasma Based Additive Copper Metallization for 3-Dimentional Ceramic Substrates in High Temperature Applications T2 - 22nd Microelectronics and Packaging Conference (EMPC) & Exhibition, 16 Sep 2019 - 19 Sep 2019, Conference Center PISA, Italy KW - 3D, KW - Kupfer KW - Sintern KW - Silbersintern KW - Sintern KW - Hochtemperatur Y1 - 2019 ER - TY - CHAP A1 - Hensel, Alexander A1 - Schwarzer, Christian A1 - Scheetz, Matthias A1 - Kaloudis, Michael A1 - Franke, Jörg T1 - Investigations of Silver Sintered Interconnections 3-Dimensional Ceramics with Plasma Based Additive Copper Metallizations T2 - 2018 IEEE 20th Electronics Packaging Technology Conference (EPTC) KW - Leistungselektronik KW - Hochtemperatur KW - Sintern Y1 - 2018 U6 - https://doi.org/10.1109/EPTC.2018.8654421 VL - 2018 SP - 416 EP - 421 CY - Singapore ER - TY - JOUR A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael A1 - Amrhein, Frank A1 - Glaab, Johannes A1 - Kaloumenos, Mareiki A1 - Sauer, Michael A1 - Gockel, Tilo T1 - LUVLED - UV-Leistungslichtquelle auf Leuchtdiodenbasis JF - Elektor Sonderheft, LEDs 2 KW - Lumineszenzdiode Y1 - 2010 VL - 2011 IS - 2 SP - 57 EP - 63 PB - Elektor-Verlag CY - Aachen ER - TY - JOUR A1 - Schneider, Johannes A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael A1 - Gockel, Tilo T1 - LUVLED III – Optimierung eines Kühlkonzeptes zur Aktivluftkühlung eines Hochleistungs-UV-LED-Moduls JF - Zeitschrift ELEKTOR, Sonderheft LED-Special 4 – Leuchtdioden in Theorie und Praxis, 2012 KW - UV-LED Modul KW - Lumineszenzdiode Y1 - 2012 IS - 9 SP - 20 EP - 29 ER - TY - JOUR A1 - Fuchs, Christopher A1 - Schreck, Timo A1 - Kaloudis, Michael T1 - Metallographische Untersuchungen an Sn-8Zn-3Bi-Lötverbindungen JF - PLUS KW - Lötverbindung KW - Metallographie Y1 - 2011 VL - 13 IS - 10 SP - 2378 EP - 2384 ER - TY - JOUR A1 - Kefer, Stefan A1 - Sauer, Theresia A1 - Hessler, Steffen A1 - Kaloudis, Michael A1 - Hellmann, Ralf T1 - Microstructure-Based Fiber-to-Chip Coupling of Polymer Planar Bragg Gratings for Harsh Environment Applications JF - Sensors (Basel) N2 - This article proposes and demonstrates a robust microstructure-based fiber-to-chip coupling scheme for planar Bragg grating devices. A polymer planar Bragg grating substrate is manufactured and microstructured by means of a micromilling process, while the respective photonic structures are generated by employing a sophisticated single-writing UV-exposure method. A stripped standard single mode fiber is inserted into the microstructure, which is filled with a UV-curable adhesive, and aligned with the integrated waveguide. After curing, final sensor assembly and thermal treatment, the proposed coupling scheme is capable of withstanding pressures up to 10 bar, at room temperature, and pressures up to 7.5 bar at an elevated temperature of 120 °C. Additionally, the coupling scheme is exceedingly robust towards tensile forces, limited only by the tensile strength of the employed single mode fiber. Due to its outstanding robustness, the coupling scheme enables the application of planar Bragg grating devices in harsh environments. This fact is underlined by integrating a microstructure-coupled photonic device into the center of a commercial-grade carbon fiber-reinforced polymer specimen. After its integration, the polymer-based Bragg grating sensor still exhibits a reflection peak with a dynamic range of 24 dB, and can thus be employed for sensing purposes. KW - Bragg grating sensors KW - cyclic olefin copolymers KW - fiber-to-chip coupling KW - microstructures KW - micromilling Y1 - 2020 UR - https://www.mdpi.com/1424-8220/20/19/5452/htm U6 - https://doi.org/10.3390/s20195452 VL - 20 IS - 19 SP - 5452 EP - 5452 ER - TY - CHAP A1 - Kefer, Stefan A1 - Roth, Frederick A1 - Kaloudis, Michael A1 - Schmauss, Bernhard A1 - Hellmann, Ralf T1 - Monitoring of Composite Bicycle Components using Polymer Planar Bragg Gratings T2 - SMSI 2021 - Sensors and Instrumentation N2 - This study demonstrates mobile load monitoring of a composite bicycle component using an application- customized polymer planar Bragg grating sensor, evaluated by a mobile interrogation unit. After a referencing procedure, the mechanical load of a seat post is monitored while cycling through a test track. KW - Bragg Grating KW - Composites KW - Cyclic Olefin Copolymers KW - Micromilling KW - Load Monitoring KW - Bragg-Reflektor KW - Verbundwerkstoff KW - Fahrrad Y1 - 2021 UR - https://www.ama-science.org/proceedings/details/3992 SN - 978-3-9819376-4-0 U6 - https://doi.org/10.5162/SMSI2021/B9.2 SP - 161 EP - 162 PB - AMA Service GmbH CY - Wunstorf, Germany ER - TY - JOUR A1 - Amrhein, Frank A1 - Kehrer, Martin A1 - Schreck, Timo A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael T1 - More efficient curing of UV sensitive mounting materials JF - Practical metallography KW - Aushärtung Y1 - 2014 VL - 48 IS - 7 SP - 356 EP - 364 ER - TY - JOUR A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael T1 - Neuartige UV-Lichtquelle auf Leuchtdiodenbasis, Packaging und Hybridschaltungen JF - PLUS KW - Lumineszenzdiode Y1 - 2010 IS - 2 PB - Leuze-Verlag ER - TY - JOUR A1 - Dressler, Katharina A1 - Rauer, Miriam A1 - Kaloudis, Michael A1 - Dauwe, Stefan A1 - Herguth, Axel A1 - Hahn, Giso T1 - Nondestructive Characterization of Voids in Rear Local Contacts of PERC-Type Solar Cells JF - IEEE Journal of Photovoltaics N2 - In this paper, we present two nondestructive characterization methods for the detection of voids in rear local contacts of passivated emitter and rear-type solar cells, namely scanning acoustic microscopy and computer tomography. We compare both methods and include a comparison with electroluminescence measurements. It is shown in this paper that voids can easily be detected with both measurement types without any sample preparation. We found a good match of scanning acoustic microscopy (SAM) and computer tomography (CT), which is presented for this purpose for the first time. The investigation was carried out for different aluminum pastes. KW - Solarzelle Y1 - 2014 U6 - https://doi.org/10.1109/JPHOTOV.2014.2359745 VL - 2015 IS - 1 SP - 70 EP - 76 ER - TY - JOUR A1 - Wohlschlögel, Timo A1 - Kaloudis, Michael T1 - Praktische Oberflächenanalytik – Überblick über die Verfahren EDX, AES, XPS und SIMS JF - Galvanotechnik KW - Oberflächenanalyse Y1 - 2011 IS - 12 SP - 2637 EP - 2646 ER - TY - JOUR A1 - Kefer, Stefan A1 - Sauer, Theresia A1 - Hessler, Steffen A1 - Kaloudis, Michael A1 - Schmauß, Bernhard A1 - Hellmann, Ralf T1 - Robust Polymer Planar Bragg Grating Sensors Embedded in Commercial-Grade Composites JF - Polymers N2 - This contribution demonstrates the functionality of polymer planar Bragg grating (PPBG) sensors integrated into commercial-grade carbon fiber reinforced polymer (CFRP) components. Multiple CFRP specimens are generated by curing a stack of pre-impregnated fibers inside of a heated mechanical press, exposing the polymer sensor to a pressure of 7 bar and a temperature of 120 °C for 2 h. After integration, the sensor still exhibits a strong and evaluable signal. Subsequent flexural experiments reveal a linear response of the integrated sensor’s Bragg wavelength to the CFRP specimen’s maximum deflection. Additional findings demonstrate that the embedded PPBG can be used to detect plastic deformations of a CFRP workpiece, whereas a linear correlation of plastic deformation to the resulting Bragg signal offset is determined. A plausibility check of the obtained results is delivered by a comparison of three-point flexural experiments on bulk CFRP workpieces, without integrated sensors and additional specimens featuring external optical sensors affixed to their surface. It is found that PPBGs based on cyclic olefin copolymers are able to overcome the temperature-related limitations of traditional polymer-based optical sensors and can thus be directly integrated into commercial-grade composites during production. KW - Bragg grating sensors KW - carbon fiber reinforced polymers KW - cyclic olefin copolymers KW - Bragg-Reflektor KW - Optischer Sensor Y1 - 2020 UR - https://www.mdpi.com/2073-4360/12/3/715/htm U6 - https://doi.org/10.3390/polym12030715 VL - 12 IS - 3 SP - 715 EP - 715 ER - TY - CHAP A1 - Rauer, Miriam A1 - Schreck, Timo A1 - Härter, Stefan A1 - Kaloudis, Michael T1 - The Effect of Thermal Stress on the Reliability of low Ag Solder Joints in High Power LEDs T2 - 20th European Microelectronics and Packaging Conference (EMPC) & Exhibition, 14.-16.09.2015 KW - Lumineszenzdiode KW - Thermische Belastung KW - Zuverlässigkeit KW - Lötverbindung Y1 - 2015 SP - 1 EP - 6 ER - TY - JOUR A1 - Amrhein, Frank A1 - Kehrer, Martin A1 - Schreck, Timo A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael T1 - UV-LED-Bestrahlung von Vergussmaterial: Schnelle Aushärtung auch im Schatten JF - adhäsion KLEBEN & DICHTEN KW - Lumineszenzdiode Y1 - 2011 IS - 5 SP - 38 EP - 41 ER - TY - JOUR A1 - Amrhein, Frank A1 - Bochtler, Ulrich A1 - Hellmann, Ralf A1 - Kaloudis, Michael A1 - Kaloumenos, Mareiki T1 - Vergleich der thermischen Eigenschaften unterschiedlicher insulated metal substrat-Leiterplatten JF - PLUS, Leiterplattentechnik KW - Gedruckte Schaltung KW - Trägersubstanz Y1 - 2010 IS - 8 SP - 1758 PB - Hanser Verlag CY - München ER - TY - JOUR A1 - Rauer, Miriam A1 - Schreck, Timo A1 - Kaloudis, Michael T1 - X-Ray Computed Tomography as Supporting Technology in the Failure Analysis of Press-In Connections for Electronic Assemblies JF - Practical Metallography KW - X-ray KW - Fehleranalyse KW - Computertomografie KW - Elektronische Baugruppe Y1 - 2013 VL - 50(2013) IS - 3 SP - 205 EP - 221 ER -