TY - CONF A1 - Mieller, Björn T1 - Glass-ceramic composite multilayer structures - modeling of densification and shrinkage mismatch N2 - Low temperature co-fired ceramics (LTCC) are glass-ceramic composites that are processed by tape casting and multilayer technology to create multilayer circuit boards and electronic packages for high frequency applications, microsystems, and sensors. Pressure-assisted sintering (PAS) enables the densification of LTCC without lateral shrinkage, and thereby the manufacturing of miniaturized modules with minimal shrinkage tolerances. Co-firing of LTCC with other functional ceramics facilitates the implementation of innovative module concepts. The master sintering curve model is a useful tool to supplement the empirical optimization of such sintering processes. Two applications of the model are presented. Firstly, an algorithm is deduced that allows the simulation of shrinkage mismatch in a combined multilayer structure. Based on this simulation, an optimized process for the co-firing of LTCC and ferrite is derived. Secondly, the pressure-assisted sintering of LTCC is modeled. A comprehensive description of the densification behavior of LTCC during PAS is thereby possible. T2 - 14. Treffen des DGG-DKG Arbeitskreises "Glasig-kristalline Multifunktionswerkstoffe" CY - Berlin, Germany DA - 25.02.2016 KW - low temperature co-fired ceramics KW - master sintering curve KW - pressure-assisted sintering KW - multilayer PY - 2016 AN - OPUS4-35419 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mieller, Björn A1 - Rabe, Torsten T1 - Structuring of LTCC Substrates by a Combination of Pressure-Assisted Sintering and Hot Embossing JF - Journal of Ceramic Science and Technology N2 - A novel technology for the structuring of low temperature co-fired ceramic (LTCC) surfaces is introduced. The commercial LTCC Ceramtape GC is shaped in a zero-shrinkage process by embossing a glass-like carbon mold into the softened LTCC during pressure-assisted sintering. Diverse raised and lowered structures including rings, grids, and characters were fabricated. It was found that de-airing of mold cavities is crucial for the molding of embossments. De-airing is possible through pore channels in the LTCC if embossing is performed at intermediate temperatures. The influence of LTCC viscosity on the mold filling behavior during the formation of raised structures is discussed. For accurate molding and proper densification of the LTCC, hot embossing with 0.41 MPa at 775 °C and subsequent heating under load to 850 °C is proposed. Embossing of precise, 40 µm deep circular cavities and 50 µm high raised bars and characters is demonstrated. Thereby, the high potential of the hot-embossing process for micro-patterning of LTCC is illustrated. KW - low temperature co-fired ceramics KW - glass-like carbon KW - hot-embossing KW - pressure-assisted sintering PY - 2015 DO - https://doi.org/10.4416/JCST2015-00051 N1 - Geburtsname von Mieller, Björn: Brandt, B. - Birth name of Mieller, Björn: Brandt, B. VL - 06 IS - 04 SP - 273 EP - 278 AN - OPUS4-35420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -