Our website is currently undergoing maintenance. This page provides
access to the published issues in the meantime. Article submissions are unaffected and
can be made through the
Editorial Manager.
Journal of Ceramic Science and Technology 4/2015
Vol. 6, No. 4 · December 2015
Thermography and Complementary Measurements as Tools to Detect Micro-Irregularities in Electronic Components
S. Röhrig, S. Röhrig, I. Petschenig, I. Petschenig, R. Bermejo, M. Hofstätter, F. Aldrian, R. Danzer, P. Supancic, P. Supancic
Pages 255-260 · DOI: 10.4416/JCST2015-00052
In many ceramic components for electrical applications, small defects in the microstructure may cause an anomalous current flow. Especially in components exhibiting nonlinear electro-thermal properties, such as varistors, positive (PTC) or negative (NTC) temperature coefficient resistors, inhomogeneities lead to high concentrations of current and localized heat generation owing to positive feedback effects. While the integral behaviour of those components is largely unaffected by these defects, the local load at these hot spot regions is extremely high and can even lead to the complete failure …
Stress and Strain Modeling of Low-Temperature Cofired Ceramic (LTCC) Seal Frame and Lid
D. Krueger, J. Porter, K. Peterson
Pages 261-266 · DOI: 10.4416/JCST2015-00064
Low-temperature cofired ceramic (LTCC) is established as an excellent packaging technology for high-reliability, high-density microelectronics. LTCC multichip modules (MCMs) comprising both 'surface mount' and 'chip and wire' technologies provide additional customization for performance. Long-term robustness of the packages is impacted by the selection of the seal frame and lid materials used to enclose the components inside distinct rooms in LTCC MCMs. An LTCC seal frame and lid combination has been developed that is capable of meeting the sealing and electromagnetic shielding requirements of …
Tolerance-Optimized RF Structures in LTCC for mm-Wave Frequencies Applications
J. Balcells-Ventura, T. Klein, P. Uhlig, C. Günner, R. Kulke
Pages 267-272 · DOI: 10.4416/JCST2015-00058
Low-Temperature Co-fired Ceramic (LTCC) is a well-established technology for microwave space products and RF structures and it is a good candidate for these new frequency bands. Embedded passives are available to increase the density of integration even more. At higher frequencies, structures become smaller and more prone to process tolerances. This challenge is addressed here with two novel mm-wave tolerance-optimized RF concepts in LTCC: load termination and Gysel power splitter. The concept presented here minimizes the effect of fabrication tolerances to provide stable RF response.
Structuring of LTCC Substrates by a Combination of Pressure-Assisted Sintering and Hot Embossing
B. Brandt, T. Rabe
Pages 273-278 · DOI: 10.4416/JCST2015-00051
A novel technology for structuring low-temperature co-fired ceramic (LTCC) surfaces is introduced. The commercial LTCC Ceramtape GC was 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 …
A 10 MHz to 80 GHz Low-Temperature Cofired Ceramic Ball Grid Array Board-to-Interposer Transition for Chip Scale Packages
B.A. Thrasher, W.E. McKinzie III, D.M. Nair, M.A. Smith, A. Beikmohamadi, E.D. Hughes, and J.M. Parisi
Pages 279-284 · DOI: 10.4416/JCST2015-00054
Presented here are the design, fabrication, and measurement results of a low-temperature cofired ceramic (LTCC) board-to-interposer transition utilizing a flip-chip ball grid array (BGA) interconnect that provides excellent electrical performance up to and including 80 GHz. A test board is fabricated in LTCC and another smaller LTCC part is used as an interposer for demonstration purposes. This BGA board-to-interposer interconnect is designed as a back-to-back pair of transitions with an assembly consisting of an LTCC interposer, an LTCC motherboard, and a BGA interconnect constructed with 260 …
Micro-Positioning Stages for Adaptive Optics Based on Piezoelectric Thick Film Actuators
S. Gebhardt, D. Ernst, B. Bramlage, O. Pabst, A. Oberdörster
Pages 285-290 · DOI: 10.4416/JCST2015-00060
Piezoceramic actuators based on thick film technology offer the opportunity of integrated solutions for smart microsystems. Especially in adaptive micro-optics, where the height of devices is limited, outgassing has to be inhibited and complex actuator structures are required, screen-printed actuators are of great interest. The paper highlights our recent research on micro-positioning stages for integration into a plenoptic camera. The first concept is based on through-thickness polarized lead zirconate titanate (PZT) thick films printed on a 45 mm x 44 mm x 0.17 mm LTCC (Low-Temperature Cofir …
Materials and Processes of Microelectronic Packaging including Low-Temperature Cofired Ceramics Technology (Past, Present and Future)
Y. Imanaka
Pages 291-300 · DOI: 10.4416/JCST2015-00050
As semiconductor technology advances and computers become smaller with higher functionality, the technology has extended into a variety of areas, such as Information Technology (IT)-enabled household electronics, Information Communication Technology (ICT) devices, electronic automobiles and Intelligent Transport Systems (ITS) transport networks, to enrich people's lives. Packaging technology serves as a vital bridge between semiconductor chips and computer systems. Its considerable value is recognized in the constant contributions it makes in bringing about a prosperous life. This paper addres …
Design, Fabrication and Characterization of Heat Spreaders in Low-Temperature Co-Fired Ceramic (LTCC) utilizing Thick Silver Tape in the Co-Fire Process
T. Welker, S. Günschmann, N. Gutzeit, J. Müller
Pages 301-304 · DOI: 10.4416/JCST2015-00042
Heat spreading in LTCC is commonly realized by means of screen-printed thick film metallization. However, the cross-sectional area of the spreading structure is technologically limited. In the presented investigation, a thick silver tape is used to form a thick silver heat spreader through the LTCC substrate. An opening is structured by laser cutting in the LTCC tape and filled with a laser-cut silver tape. After lamination, the substrate is fired in a constraint sintering process. The bond strength of the silver to LTCC interface is approx. 5.6 MPa. The thermal resistance of the silver struct …
Small-Size Low-Loss Bandpass Filters on Substrate-Integrated Waveguide Capacitively Loaded Cavities Embedded in Low Temperature Co-Fired Ceramics
V. Turgaliev, D. Kholodnyak, J. Müller, and M.A. Hein
Pages 305-314 · DOI: 10.4416/JCST2015-00053
The design of microwave filters for portable electronics is complicated by conflicting requirements that must be met simultaneously such as high selectivity, low insertion loss and compact size. Substrate-integrated waveguide (SIW) technology allows the design of low-profile high-Q resonators and low-loss filters based on this. However, SIW filters are not well suited for telecommunication applications because of their remarkably large size in plane. The size of a SIW cavity can be dramatically reduced with the use of capacitive loading. Capacitively loaded cavities (CLCs) operating in the TM1 …
LTCC-Based Multi-Electrode Arrays for 3D in Vitro Cell Cultures
H. Bartsch, M. Himmerlich, M. Fischer, L. Demkó, J. Hyttinen, A. Schober
Pages 315-324 · DOI: 10.4416/JCST2015-00056
Current technologies to monitor neuronal cultures in vitro are based on 2-dimensional (2D) multi-electrode arrays and cell cultures. The complexity of actual high-level neurobiological systems requires 3-dimensional (3D) cultures and 3D electrode arrays to improve our understanding of such systems. The realization calls for smart multilayer and packaging technology. Our approach uses low-temperature cofired ceramics (LTCC) for the design of a 3-dimensional multi-electrode array (3D MEA). An LTCC multilayer board with gold electrodes forms the basis of the system. The layout of the 3D MEA is de …
DuPont 9k7 low-temperature cofired ceramic (LTCC) is a low-loss, or high-quality-factor Q, tape system targeting at radio frequency (RF) applications. This paper reports on the effect of a critical process parameter, the heating rate, on the densification and dielectric properties of the 9k7 LTCC. The role of competing densification and crystallization during the sintering of 9k7 is discussed. The high Q of DuPont 9K7 can be used to improve RF system performance, for example a better receiver noise figure, by designing embedded passive RF components such as inductors, capacitors and filters. M …
3D Focalization Microfluidic Device Built with LTCC Technology for Nanoparticle Generation using Nanoprecipitation Route
H.C. Gomez, M.R. Gongora-Rubio, B.O. Agio, J. de Novais Schianti, V. Tiemi Kimura, A- Marim de Oliveira, L. Wasnievski da Silva de Luca Ramos, A.C. Seabra
Pages 329-338 · DOI: 10.4416/JCST2015-00062
Nanoprecipitation is a nanonization technique used for generating nanoparticles. Fields like pharmaceuticals and fine chemistry make use of such techniques. Typically, bulky batch mechanical processes are used, but these result in a high polydispersity index of the generated nanoparticles, poor particle size reproducibility and energy waste.LTCC-based microsystem technologies allow the implementation of different unitary operations for the chemical process, making it an enabling technology for miniaturization. In fact, LTCC microfluidic reactors have recently been used to produce micro- and na …
