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 - JOUR A1 - Naghib Zadeh, Hamid A1 - Rabe, Torsten A1 - Karmazin, R. T1 - Integration of MnZn-ferrite tapes in LTCC multilayer N2 - For co-firing of MnZn-ferrite tapes and LTCC dielectric tapes, the sintering shrinkage curves and the coefficient of thermal expansion of ferrite and dielectric tapes were matched. Highly densified embedded ferrite without any cracks could be manufactured by co-firing at 900 °C in nitrogen atmosphere. However, the permeability of MnZn-ferrite co-fired between dielectric tapes is significantly reduced (µ´=100) compared to that of the separately sintered ferrite (µ´=500). Changes in the phase stability and microstructure of MnZn-ferrite were investigated to explain the permeability reduction in the embedded ferrite. It is supposed that early densification of the dielectric tapes on the top and bottom of the ferrite layer prevent the gas exchange during sintering which is necessary for (Mn,Zn)Fe2O4 spinel formation. As a result, high amount of Fe2O3 secondary phase and a Mn-rich spinel phase with low permeability remain in the embedded ferrite layer. KW - LTCC KW - MnZn-ferrite KW - Co-firing PY - 2013 DO - https://doi.org/10.1007/s10832-013-9800-5 SN - 1385-3449 SN - 1573-8663 VL - 31 IS - 1-2 SP - 88 EP - 95 PB - Kluwer Acad. Publ. CY - Boston, Mass. [u.a.], USA AN - OPUS4-29385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -