TY - JOUR A1 - Gaebler, A. A1 - Moessinger, A. A1 - Goelden, F. A1 - Manabe, A. A1 - Goebel, M. A1 - Follmann, R. A1 - Koether, D. A1 - Modes, C. A1 - Kipka, A. A1 - Deckelmann, M. A1 - Rabe, Torsten A1 - Schulz, Bärbel A1 - Kuchenbecker, Petra A1 - Lapanik, A. A1 - Mueller, S. A1 - Haase, W. A1 - Jakoby, R. T1 - Liquid crystal-reconfigurable antenna concepts for space applications at microwave and millimeter waves JF - International journal of antennas and propagation N2 - Novel approaches of tunable devices for millimeter wave applications based on liquid crystal (LC) are presented. In the first part of the paper, a novel concept of a tunable LC phase shifter realized in Low Temperature Cofired Ceramics technology is shown while the second part of the paper deals with a tunable high-gain antenna based on an LC tunable reflectarray. The reflectarray features continuously beam scanning in between ±25°. Also first investigations on radiation hardness of LCs are carried out, indicating that LCs might be suitable for space applications. KW - Tunable antenna KW - Phase shifter KW - Liquid crystal KW - LTCC PY - 2009 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-194273 DO - https://doi.org/10.1155/2009/876989 SN - 1687-5877 VL - 2009 IS - Article ID 876989 SP - 1 EP - 7 PB - Hindawi Publishing Corporation CY - New York, NY, USA AN - OPUS4-19427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Glitzky, Carsten A1 - Rabe, Torsten A1 - Eberstein, Markus A1 - Schiller, Wolfgang Arno A1 - Töpfer, J. A1 - Barth, S. A1 - Kipka, A. T1 - LTCC-Modules with integrated ferrite layers - Strategies for material development and co-sintering JF - Journal of microelectronics and electronic packaging N2 - The integration of passive components (resistors, capacitors, inductors) into LTCC modules is a challenging task in multilayer ceramics technology. We report on multilayer assemblies consisting of combined layers of ferrite and dielectric LTCC tapes. Ni-Cu-Zn ferrites with maximum shrinkage at 900°C were processed to green tapes and laminated with dielectric LTCC tapes. Cosintering at 900°C led to multilayers with different defects such as incomplete densification of the ferrite layers, cracks, and warpage. Since ferrite tapes do not really allow compositional changes without deterioration of magnetic properties, the dielectric tape was modified with the following objectives: (i) matching of the shrinkage curves of dielectric and ferrite materials, (ii) adjusting the coefficients of thermal expansion to avoid cracking during cooling, and (iii) controlling of interface reactions. Using this concept we fabricated dense and defect-free multilayers consisting of dielectric and ferrite layers. However, compositional changes of the individual ferrite tapes require the development of a specific dielectric tape material with tailored properties. KW - Coefficient of thermal expansion (CTE) KW - Cofiring KW - Ferrite KW - LTCC KW - Shrinkage PY - 2009 SN - 1551-4897 VL - 6 IS - 1 SP - 49 EP - 53 CY - Washington, DC AN - OPUS4-19708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Glitzky, Carsten A1 - Rabe, Torsten A1 - Eberstein, Markus A1 - Schiller, Wolfgang Arno A1 - Töpfer, J. A1 - Barth, S. A1 - Kipka, A. T1 - LTCC-modules with integrated ferrite layers - Strategies for material development and co-sintering T2 - CICMT 2008 - 4th International Conference and Exhibition on Ceramic Interconnect and Ceramic Microsystems Technologies, April 21-24, 2008, Munich, Germany (Proceedings) T2 - 2009 IMAPS/ACerS - 5th International Conference and Exhibition on Ceramic Interconnect and Ceramic Microsystems Technologies (CICMT) CY - Denver, Colorado, USA DA - 2009-04-21 KW - LTCC KW - Ferrite KW - Co-firing KW - Shrinkage KW - Coefficient of thermal expansion (CTE) PY - 2008 SN - 0-930815-83-1 SP - 000058 EP - 000063 AN - OPUS4-18926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -