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 - 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 -