TY - CONF A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten T1 - Pressure-Assisted Sintering of Multilayer Transformer Using LTCC-Compatible NiCuZn-Ferrite and Silver Conductor T2 - Ceramic Interconnect and Ceramic Microsystems Technologies (CICMT) 2012 CY - Erfurt, Germany DA - 2012-04-17 PY - 2012 AN - OPUS4-25749 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mieller, Björn A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten T1 - Improved co-firing of ferrite and dielectric tape based on master sintering curve predictions and shrinkage mismatch calculations N2 - Co-firing of low temperature co-fired ceramics (LTCC) and functional ceramics like ferrites is a promising approach to increase the level of integration in future microsystems, and to create new applications for LTCC technology. Besides the development of compatible material combinations, the configuration of the sintering process is an important issue for successful co-firing. A method is presented to derive the linear shrinkage mismatch of a material combination based on density data calculated from the master sintering curves (MSCs) of the individual materials. The influence of the firing profile on the constraint in the combined multilayer can be anticipated using this method. To investigate and improve the co-firing of ferrite and dielectric tape, the shrinkage mismatch with respect to heating rate was studied. A significant reduction of shrinkage mismatch was found for increased heating rates. The calculated results are verified by lateral shrinkage measurements on combined laminates. PY - 2013 U6 - https://doi.org/10.1111/jace.12179 SN - 0002-7820 SN - 1551-2916 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. VL - 96 IS - 3 SP - 726 EP - 730 PB - Blackwell Publishing CY - Malden AN - OPUS4-27955 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten A1 - Barth, S. A1 - Töpfer, J. T1 - Characterization of NiCuZn ferrite layer co-fired with LTCC dielectric tapes T2 - 13th International Conference of the European Ceramic Society CY - Limoges, France DA - 2013-06-23 PY - 2013 AN - OPUS4-28839 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rabe, Torsten A1 - Naghib Zadeh, Hamid A1 - Glitzky, C. A1 - Töpfer, J. T1 - Integration of Ni-Cu-Zn ferrite in LTCC-modules N2 - Integration of magnetic functional components in LTCC Circuit boards calls for co-firing of dielectric and ferrite tapes. Ni-Cu-Zn ferrites with permeability of p=900 were developed which can be fully densified at the Standard LTCC sintering temperature of 900 °C. Successful co-firing of this ferrite with dielectric tapes requires the adaptation of the shrinkage behavior of the materials as well as the thermal expansion during the cooling period - especially in the temperature range below the transformation point of the glassy phase of the dielectric tape. To match these preconditions, a new dielectric LTCC material with steep sintering curve and high thermal expansion coefficient was designed. Sintered multilayer composed of Ni-Cu-Zn ferrite and tailored dielectric tapes are free of cracks and possess no open porosity. No significant interdiffusion between the ferrite and dielectric tapes was found by EDX measurements. Compared to pure ferrite laminates the permeability of co-sintered Ni-Cu-Zn ferrite layers is drastically reduced to 400, i.e. a decrease of more than 50 %. To investigate the origin of this permeability reduction, Ni-Cu-Zn ferrite laminates were sintered separately, and in combination with alumina release tapes or dielectric tapes, respectively. SEM and EDX analysis of co-fired laminates reveal differences in the ferrite grain growth behavior. Ferrite laminates with homogeneous microstructure and grain size up to 50 pm exhibit large permeability. However, growth of ferrite grains does not take place near the interface between ferrite and release or dielectric tapes. There is a strong correlation between high permeability and volume fraction of large ferrite grains. Regions of fine and coarse grains inside the ferrite layers show different bismuth concentration; the Bi-content is larger in regions of fine ferrite grains. T2 - CICMT 2011 - 7th International conference and exhibition on ceramic interconnect and ceramic microsystems technologies CY - San Diego, CA, USA DA - 05.04.2011 KW - LTCC KW - Co-firing KW - Ferrite KW - Shrinkage behavior KW - Constrained sintering KW - Keramische Multilayer KW - Grenzflächenreaktion PY - 2011 SN - 0-930815-92-0 SP - 000266 EP - 000275 PB - IMAPS, International Microelectronics and Packaging Society AN - OPUS4-25072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten A1 - Töpfer, J. A1 - Karmazin, R. T1 - Co-Firing of LTCC Modules with Embedded Ferrite Layers T2 - European Microelectronics Packaging Conference CY - Brighton, England DA - 2011-09-12 PY - 2011 AN - OPUS4-24867 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten A1 - Toepfer, J. A1 - Karmazin, R. T1 - Co-firing of LTCC modules with embedded ferrite layers N2 - Further miniaturization of electronic packaging calls for integration of magnetic functional components into LTCC modules. For integration of magnetic function into LTCC, low fired MnZn- and NiCuZn-ferrites which can be fully densified at the standard LTCC sintering temperature of 900°C were developed. To co-fire these ferrite tapes with dielectric tapes the sintering shrinkage and the coefficient of thermal expansion of ferrite and dielectric tapes must be matched. For each ferrite material a new LTCC dielectric material was designed. The embedded ferrite tapes into new LTCC dielectric tapes can be sufficiently densified during co-firing at 900°C without any cracking. Compared to separately sintered ferrites the permeability of embedded ferrite tapes is reduced. For embedded NiCuZn ferrites permeabilities between 230 and 570 (at 2 MHz) according to the thickness of the embedded ferrite layer were measured. For embedded MnZn ferrites a permeability of 300 was measured. T2 - EMPC-2011 - 18th European microelectronics & packaging conference CY - Brighton, UK DA - 12.09.2011 KW - LTCC KW - Co-firing KW - Ferrite PY - 2011 SN - 978-0-9568086-0-8 IS - TuA2 SP - 1 EP - 6 AN - OPUS4-25021 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Mieller, Björn A1 - Rabe, Torsten A1 - Töpfer, J. T1 - Anwendung der Master-Sinter-Kurve bei der Co-Sinterung von Werkstoffkombinationen T2 - Jahrestagung der Deutschen Keramischen Gesellschaft 2012 CY - Nuremberg, Germany DA - 2012-03-05 PY - 2012 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. AN - OPUS4-25517 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, Torsten A1 - Naghib Zadeh, Hamid A1 - Glitzky, Carsten A1 - Töpfer, J. T1 - Integration of Ni-Cu-Zn ferrite in low temperature Co-fired ceramics (LTCC) modules N2 - Integration of magnetic functional components in LTCC circuit boards calls for co-firing of dielectric and ferrite tapes. Ni-Cu-Zn ferrites with permeability of µ = 900 were fully densified at the standard LTCC sintering temperature of 900°C. Co-firing of this ferrite with dielectric tapes requires the adaptation of the shrinkage behavior of the materials as well as the thermal contraction during the cooling period – especially in the temperature range below the transformation point of the glass phase of the dielectric tape. To match these preconditions, a new dielectric LTCC material with steep sintering curve and high thermal expansion coefficient was designed. Sintered multilayer laminates composed of Ni-Cu-Zn ferrite and tailored dielectric tapes are free of cracks and possess no open porosity. No significant interdiffusion between the ferrite and dielectric tapes was found using microprobe analysis. Pure ferrite laminates show homogeneous microstructure with large grains up to 50 µm in diameter. However, growth of ferrite grains does not take place near the interface between ferrite and release or dielectric tapes. There is a strong correlation between permeability and volume fraction of large ferrite grains. Compared to pure ferrite laminates the permeability of co-sintered Ni-Cu-Zn ferrite layers is drastically reduced to 400, that is a decrease of more than 50%. PY - 2012 U6 - https://doi.org/10.1111/j.1744-7402.2011.00712.x SN - 1546-542X SN - 1744-7402 VL - 9 IS - 1 SP - 18 EP - 28 PB - American Ceramic Soc. CY - Westerville, Ohio AN - OPUS4-25544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten T1 - Pressure-assisted sintering of multilayer transformer using LTCC-compatible NiCuZn-ferrite and silver conductor T2 - CICMT 2012 - 8th International conference on ceramic interconnect & ceramic microsystems technologies CY - Erfurt, Germany DA - 2012-04-16 KW - LTCC KW - Ferrite KW - Silver conductor PY - 2012 SP - 000476 EP - 000483 (Session WP 1 / WP 15) AN - OPUS4-27775 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Naghib Zadeh, Hamid A1 - Glitzky, Carsten A1 - Rabe, Torsten T1 - Development of capacitor materials with sintering temperature below 900°C T2 - 10th Intern. Conf. of the European Ceramic Soc., ECerS 2007 CY - Berlin, Germany DA - 2007-06-17 PY - 2007 AN - OPUS4-16201 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -