TY - CONF A1 - Heunisch, Andreas T1 - In-situ-Analyse des Sinterverhaltens von LTCC-Multilayern mit vergrabenen Kavitäten mittels Hochtemperatur-Laserprofilometrie (HTLP) T2 - Jahrestagung der Deutschen Keramischen Gesellschaft 2014 CY - Clausthal-Zellerfeld, Germany DA - 2014-03-24 PY - 2014 AN - OPUS4-30459 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jost, M. A1 - Strunck, S. A1 - Heunisch, Andreas A1 - Wiens, A. A1 - Prasetiadi, A.E. A1 - Weickhmann, C. A1 - Schulz, Bärbel A1 - Quibeldey, M. A1 - Karabey, O.H. A1 - Rabe, Torsten A1 - Follmann, R. A1 - Koether, D. A1 - Jakoby, R. T1 - Continuously tuneable liquid crystal based stripline phase shifter realised in LTCC technology N2 - This work presents the design, fabrication and measurements of a low temperature cofired ceramic (LTCC) integrated liquid crystal (LC) phase shifter. The effective permittivity of the phase shifter and therefore its differential phase shift can be tuned continuously by orienting the LC directors with electric fields. The phase-shift demonstrator is designed for Ka-band frequencies around 30 GHz and represents a stripline filled with LC, embedded inside an LTCC multilayer structure, which provides a space-qualified and hermetically-sealed LC cavity within an RF-capable material system. The total length of the device is 37 mm while the phase shifting LC section has a length of 14.6 mm. At 30 GHz it exhibits a differential phase shift of 60° with an insertion loss around 6 dB, resulting in a figure of merit around 10°/dB. An advantage is that the insertion loss is nearly independent of the tuning state of the LC. The response time of the phase shifter, depending on the desired LC orientation, is between 62 ms and 37 s. T2 - EuMC 2015 - 45th European microwave conference CY - Paris, France DA - 07.09.2015 PY - 2015 SN - 978-2-87487-039-2 SP - 1260 EP - 1263 AN - OPUS4-35268 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas A1 - de Seauve, Victor A1 - Rabe, Torsten T1 - Pressure-assisted sintering of buried thick film resistors in LTCC N2 - In this work, the effect of the pressure-assisted sintering process on buried thick film resistors integrated in LTCC multilayer has been studied. Four commercial resistor pastes with sheet resistivities between 10 kΩ and 10 MΩ/cm were analyzed. First they were characterized by SEM/EDX, XRD and Laser diffraction to determine composition and particle distribution. The pastes consist of isolating particles and of Ruthenium based particles that are supposed to build the conductive phase. The pastes were screen printed on LTCC green tape (DP 951) and buried in four layer laminates. Sintering was done in two ways, pressureless (PLS) and also pressure-assisted (PAS). The pressureless sintered resistors showed electrical resistance values roughly in the range of the nominal sheet resistivity and only relatively small fluctuation within one sample. The PAS samples on the other hand showed significantly higher resistances and larger deviations. The microstructure of the sintered resistors was again investigated by SEM and XRD. It seems that the resistivity is determined by the ratio of the two Ruthenium phases RuO2 and Pb2Ru2O6.5, where RuO2 has the higher conductivity. Buried resistors cannot be trimmed by a laser to adjust the resistance. But we discovered that a refiring step will reduce and normalize the resistivity of the PAS resistors significantly. T2 - IMAPS/ACerS 11th International CICMT conference and exhibition CY - Dresden, Germany DA - 20.04.2015 KW - LTCC Multilayer KW - Buried thick film resistors KW - Pressure-assisted sintering PY - 2015 SN - 978-1510804562 DO - https://doi.org/10.4071/CICMT-WP21 SP - 239 EP - 244 AN - OPUS4-35254 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas A1 - Francke, T. T1 - LIQUIDA-Sky Project: Electronically Tunable Filters for K-Band Satellites based on Microwave Liquid Crystal Technology T2 - 4. Nationale Konferenz - Satellitenkommunikation in Deutschland CY - Bonn, Germany DA - 2015-03-25 PY - 2015 AN - OPUS4-32924 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - Pressure-Assisted Sintering of Buried Thick Film Resistors in LTCC T2 - IMAPS/ACerS 11th International Conference and Exhibition on Ceramic Interconnect and Ceramic Microsystem Technologies (CICMT 2015) CY - Dresden, Germany DA - 2015-04-20 PY - 2015 AN - OPUS4-33091 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - LTCC mit integrierten Widerstandselektroden für ein steuerbares Hochfrequenz-Filter T2 - 90. Jahrestagung der Deutschen Keramischen Gesellschaft (DKG) CY - Bayreuth, Deutschland DA - 2015-03-15 PY - 2015 AN - OPUS4-32853 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strunck, S. A1 - Gaebler, A. A1 - Karabey, O.H. A1 - Heunisch, Andreas A1 - Schulz, Bärbel A1 - Rabe, Torsten A1 - Follmann, R. A1 - Kassner, J. A1 - Koether, D. A1 - Manabe, A. A1 - Jakoby, R. T1 - Reliability study of a tunable ka-band SIW-phase shifter based on liquid crystal in LTCC-technology N2 - A tunable substrate-integrated waveguide phase shifter using low-temperature co-fired ceramic (LTCC)-technology is presented in this paper. By changing the effective permittivity in the liquid crystal (LC)-filled waveguide, the differential phase can be tuned continuously. This is achieved by means of an analog signal applied to the electrodes, surrounding the LC. The design allows for precise tuning of the differential phase, which is proven with a Monte Carlo measurement resulting in phase errors of less than 3° at 28 GHz. Besides that, the ambient temperature dependency of the module is shown. The phase shifter has a high integration level and can be included into a complete and lightweight single-phased array antenna module. The phase shifter is realized with a high level of integration which is available through the multilayer process of the LTCC. It has a length of 50 and provides a differential phase shift of more than 360° at 28 GHz. The figure of merit for tunable phase shifters is >40°/dB. KW - Passive components and circuits KW - New and emerging technologies and materials PY - 2014 DO - https://doi.org/10.1017/S175907871400083X SN - 1759-0787 SN - 1759-0795 SP - 1 EP - 7 PB - Cambridge Univ. Press CY - Cambridge AN - OPUS4-31198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nikfalazar, M. A1 - Kohler, C. A1 - Heunisch, Andreas A1 - Wiens, A. A1 - Zheng, Y. A1 - Schulz, Bärbel A1 - Mikolajek, M. A1 - Sohrabi, M. A1 - Rabe, Torsten A1 - Binder, R. A1 - Jakoby, R. T1 - LTCC phase shifters based on tunable ferroelectric composite thick films N2 - This paper presents, the investigation of tunable components based on LTCC technology, implementing ferroelectric tunable thick-film dielectric. The tunable loaded line phase shifters are fabricated with metal-insulator-metal (MIM) varactors to demonstrate the capabilities of this method for packaging of the tunable components. The MIM varactors consist of one tunable dielectric paste layer that is printed between two silver layers. The tunable ferroelectric paste is optimized for LTCC sintering temperature around 850°C. The phase shifters are fabricated in two different process. They were achieved a figure of merit of 24°/dB (phase shift 192°) at 3 GHz and 18°/dB (phase shift 98°) at 4.4 GHz by using seven unit cells that each unit cell consisting of two MIM varactors. KW - Ferroelectric KW - LTCC KW - Phase shifter KW - Fully printed component KW - BST PY - 2015 DO - https://doi.org/10.1515/freq-2015-0082 SN - 0016-1136 SN - 2191-6349 VL - 69 IS - 11-12 SP - 451 EP - 455 PB - De Gruyter CY - Berlin ; Boston, Mass. AN - OPUS4-34949 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - LTCC multilayer with integrated cavities for tunable microwave components T2 - 14th international conference European Ceramic Society ECERS 2015 CY - Toledo, Spain DA - 2015-06-22 PY - 2015 AN - OPUS4-33538 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kohler, C. A1 - Nikfalazar, M. A1 - Heunisch, Andreas A1 - Schulz, Bärbel A1 - Mikolajek, M. A1 - Rabe, Torsten A1 - Jakoby, R. A1 - Binder, J. T1 - Implementation of Ba0.6Sr0.4TiO3-ZnO-B2O3 based tunable microwave phase shifters in LTCC technology N2 - Tunable dielectric Ba0.6Sr0.4TiO3-ZnO-B2O3 thick-films were analyzed regarding their integration potential into the LTCC technology. Therefore, tunable loaded line phase shifters based on metal-insulator-metal varactors with single- and double- printed BST thick-films were fabricated and co-sintered inside a four layer LTCC module. Microstructural and chemical investigations showed a sufficient compatibility and adhesion between the silver, BST composite and LTCC layers and a resulting morphology depending on the processing route. The microwave characterization of the LTCC-embedded phase shifters revealed comparable results to phase shifters with the same design on alumina substrates. KW - Thick films KW - Dielectric materials KW - Electroceramics PY - 2017 DO - https://doi.org/10.1111/ijac.12687 SN - 1546-542X SN - 1744-7402 VL - 14 IS - 4 SP - 574 EP - 582 PB - Wiley CY - Hoboken, NY, USA AN - OPUS4-41086 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - Fabrication and Characterisation of LTCC multilayer with large embedded cavities T2 - Konferenz der European Ceramic Society CY - Stockholm, Sweden DA - 2011-06-19 PY - 2011 AN - OPUS4-23485 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - 3D-Computertomographie an keramischen Multilayern T2 - Jahrestagung der Deutschen Keramischen Gesellschaft 2012 CY - Nuremberg, Germany DA - 2012-03-05 PY - 2012 AN - OPUS4-25516 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - LTCC Antenna Array with Integrated Liquid Crystal Phase Shifter for Satellite Communication T2 - IMAPS/ACerS 8th Int. Conf. and Exhib. on Ceramic Interconnect and Ceramic Microsystems Technolgies (CICMT) CY - Erfurt, Germany DA - 2012-04-16 PY - 2012 AN - OPUS4-25754 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - Fabrication and Characterization of Low Temperature Co-fired Ceramic Multilayer with Embedded Cavities T2 - Junior Euromat 2012 CY - Lausanne, Switzerland DA - 2012-07-23 PY - 2012 AN - OPUS4-26529 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - Zerstörungsfreie Prüfung an Multilayern T2 - ZEMI summer school 2012 CY - Berlin, Germany DA - 2012-08-27 PY - 2012 AN - OPUS4-26439 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - Ceramic Multilayer - Technology and Application T2 - Klausurtagung des Graduiertenkolleg "TICMO" CY - Klingenberg, Germany DA - 2012-11-15 PY - 2012 AN - OPUS4-27046 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - Verformung von LTCC-Multilayern mit vergrabenen Kavitäten im Laminier- und Sinternprozess T2 - Jahrestagung der Deutschen Keramischen Gesellschaft CY - Weimar, Germany DA - 2013-03-18 PY - 2013 AN - OPUS4-27871 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas A1 - Marzok, Ulrich A1 - Münchow, Marco A1 - Müller, Ralf A1 - Rabe, Torsten T1 - In situ characterization of the sintering behavior of LTCC laminates with embedded cavities by high temperature laser profilometry N2 - Three-dimensionally structured LTCC multilayer with channels and inner cavities are required for numerous applications like microreactors, microfluidic systems or sensors. For the performance of such devices, the dimensional accuracy of the embedded structures is crucial. In the green state, the desired structures can be precisely implemented in the LTCC tapes by laser cutting, punching or milling. Unfortunately, during lamination and sintering, shape integrity of cavities and channels is notably affected by warpage and deformation. To investigate the sintering behavior of structured LTCC laminates, a newly developed High Temperature Laser Profilometer (HTLP) can be used. The HTLP allows 3D in-situ shape detection of flat ceramic samples and tapes all along the sintering process. It is applicable for temperatures up to 1000 °C and sample sizes up to 200 mm × 200 mm × 10 mm. During a measurement, the rotating sample is scanned spirally by a linearly moving laser distance sensor through a slot in the furnace top wall. Distance and position values deliver a 3D surface image of the sample. Current lateral dimensions, which are determined by sintering shrinkage, can be measured continuously. Local deformation and warpage can be visualized time- and temperature-resolved. This new method was used, to analyze the sintering behavior of LTCC multilayer laminates containing large size cavities. These were fabricated out of punched green sheets by low pressure lamination without inserts. Samples with cavities of varying cross sections, as well as cavities with and without connection to the surface were observed. T2 - CICMT 2013 - IMAPS/ACerS 9th International conference and exhibition on ceramic interconnect and ceramic microsystems technologies CY - Orlando, FL, USA DA - 23.04.2013 KW - LTCC multilayer KW - Embedded cavities KW - High temperature laser profilometry KW - Low pressure lamination KW - Micro fluidics PY - 2013 DO - https://doi.org/10.4071/cicmt-tha44 SP - 275 EP - 282 AN - OPUS4-35077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - In Situ Characterization of the Sintering Behavior of LTCC Laminates with Embedded Cavities by High Temperature Laser Profilometry T2 - IMAPS/ACerS 8th Int. Conf. and Exhib. on Ceramic Interconnect and Ceramic Microsystems Technolgies (CICMT 2013) CY - Orlando, FL, USA DA - 2013-04-23 PY - 2013 AN - OPUS4-29118 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heunisch, Andreas T1 - LTCC mit Kavitäten für HF-Anwendungen T2 - Sitzung des Arbeitskreis Funktionskeramik (DKG/DGM) CY - Darmstadt, Germany DA - 2014-07-17 PY - 2014 AN - OPUS4-31126 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -