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The paper aims to present numerical modeling and technology of a very first three axial low temperature cofired ceramics (LTCC) accelerometer.

Low temperature cofired ceramics technology was applied in the fabrication process of the novel device. The numerical modeling was used to predict the properties of the accelerometer, moreover, design of the experiment methodology was used to reduce time of simulation and to get as much as information from the experiment as possible.

The low temperature cofired ceramics make it possible to fabricate three axial accelerometer.

The presented device is just a first prototype. Therefore, further research work will be needed to improve structural drawbacks and to analyze precisely the device reliability and parameters repeatability.

The device presented in the paper can be applied in systems working in a harsh environment (high temperature and humidity). Ceramic sensors can withstand temperatures up to 600°C.

This paper presents novel three axial LTCC accelerometer.

One of the major driving forces for the electronic industry is the consumer handheld units, where even more functions in a smaller volume and with longer battery time are requested. This leads to a higher energy‐ and interconnect‐density. Two challenges related to this request, that the industry is facing, are thermal management and reliability. This paper aim to discuss some aspects of using flip chip (FC) technology on low temperature cofired ceramics (LTCC) for this kind of products and to focus on the heat dissipation problem of an FC mounted die.

Test designs were developed and built to investigate SnAgCu bumps on LTCC, underfill and five different LTCC designs. The LTCC design parameters were thermal vias and heat spreaders. In the experimental part, the semiconductor junction temperature was measured over a diode in the semiconductor. Cross sections and infrared thermal imaging were used. The experiments were accompanied by FE‐modeling using ANSYS workbench.

The main reduction in temperature is related to the use of thermal vias and a via offset smaller than 60 μm. A 100 μm via diameter gives only a minor increase in the semiconductor junction temperature. Reducing the LTCC substrate thickness will decrease the junction temperature further.

This paper shows that FC on LTCC is a promising key technology for power amplifier modules.

The new Low Temperature Cofired Ceramic process combines the advantages of thick film standard and cofired ceramic technologies for the implementation of high interconnection density hybrid circuits, at a reasonable cost. Due to the wide diversity of devices required in the telecommunications field, it is important to have for drilling and scribing a system capable of being easily integrated onto a LAN, in order to reduce the machine preparation time, using all the information already existing in CAD. As laser systems are standard in thick film production, the investments involved to implement a new technology are minimised. This paper describes the use of laser technology for drilling green ceramic to achieve interconnection paths between different levels, manufacturing of screen mask (via metallisation), and scribing of substrates already synthesised. A preliminary characterisation of Telettra's technology follows.

This paper aims to investigate the usability of the nickel copper zinc ferrite with the composition Ni_0.4Cu_0.2Zn_0.4Fe_1.98O_3.99 for the realization of high-temperature multilayer coils as discrete components and integrated, buried function units in low temperature cofired ceramics (LTCC).

LTCC tapes were cast and test components were produced as multilayer coils and as embedded coils in a dielectric tape. Different metallization pastes are compared. The properties of the components were measured at room temperature and higher temperature up to 250°C. The results are compared with simulation data.

The silver palladium paste revealed the highest inductance values within the study. The measured characteristics over a frequency range from 1 MHz to 100 MHz agree qualitatively with the measurements obtained from toroidal test samples. The inductance increases with increasing temperature and this influence is lower than 10%. The characteristic of embedded coils is comparable with this of multilayer components. The effective permeability of the ferrite material reaches values around 130.

The research results based on a limited number of experiments; therefore, the results should be verified considering higher sample sizes.

The results encourage the further investigation of the material Ni_0.4Cu_0.2Zn_0.4Fe_1.98O_3.99 for the use as high-temperature ferrite for the design of multilayer coils with an operation frequency in the range of 5-10 MHz and operation temperatures up to 250°C.

It is demonstrated for the first time, that the material Ni_0.4Cu_0.2Zn_0.4Fe_1.98O_3.99 is suitable for the realization of high-temperature multilayer coils and embedded coils in LTCC circuit carriers with high performance.

The purpose of this paper is to present the application of low temperature cofired ceramics (LTCC) technology in the fabrication of a novel electronic device, which consists of an antenna amplifier integrated with temperature stabilizer. The temperature controller consists of a thick‐film thermistor and heater, which has been optimized using geometry to achieve uniform temperature distribution on the whole electronic substrate.

LTCC technology was applied in the fabrication process of the novel device. The temperature distribution on the ceramic substrate and temperature stabilization time were analyzed using an IR camera. The heating ability of the heater was tested in a climatic chamber. The heater and thermistors parameters variability were estimated using a basic mathematical statistic.

The integrated device ensures proper temperature conditions of electronic components if the ambient temperature is lower than −40°C.

The presented device is just a first prototype. Therefore, the fabrication of the next structures and further experiments will be needed to improve structural drawbacks and to analyze precisely the device reliability and parameters repeatability.

The device presented in the paper can be applied in systems working at very low ambient temperatures (even at −5°C). Moreover, a temperature stabilizer can increase the temperature of the whole device above −40°C, therefore, standard electronic components (which can work down to −40°C) can be used instead of specialized ones (which can work below −40°C).

This paper presents a novel temperature stabilizer.

The purpose of this paper is to review possibilities of implementing ceramic additive manufacturing (AM) into electronic device production, which can enable great new possibilities.

A short introduction into additive techniques is included, as well as primary characterization of structuring capabilities, dielectric performance and applicability in the electronic manufacturing process.

Ceramic stereolithography (SLA) is suitable for microchannel manufacturing, even using a relatively inexpensive system. This method is suitable for implementation into the electronic manufacturing process; however, a search for better materials is desired, especially for improved dielectric parameters, lowered sintering temperature and decreased porosity.

Relatively inexpensive ceramic SLA, which is now available, could make ceramic electronics, currently restricted to specific applications, more available.

Ceramic AM is in the beginning phase of implementation in electronic technology, and only a few reports are currently available, the most significant of which is mentioned in this paper.

The work was aimed at preparation of green tapes based on a new material Bi_2/3CuTa₄O₁₂, to achieve spontaneously formation of an internal barrier layer capacitor (IBLC), fabrication of multilayer elements using low temperature cofired ceramics (LTCC) technology and their characterization.

The study focused on tape casting, lamination and co-sintering procedures and dielectric properties of Bi_2/3CuTa₄O₁₂ multilayer capacitors. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) studies of the ceramic elements were performed. Impedance spectroscopy was used for characterization of dielectric properties in the frequency range of 0.1 Hz to −2 MHz and in the temperature range from −55 to 400°C. DC conductivity was investigated in the temperature range 20 to 740°C.

SEM observations revealed a good compatibility of the applied commercial Pt paste with the ceramic layers. The EDS microanalysis showed a higher content of oxygen at grain boundaries. The dominant dielectric response, which was recorded in the low frequency range and at temperatures above 0°C, was attributed to grain boundaries. The dielectric response at low temperatures and/or high frequencies was related to grains. The fabricated multilayer capacitors based on Bi_2/3CuTa₄O₁₂ exhibited a high specific capacitance.

A new material Bi_2/3CuTa₄O₁₂ was applied for preparation of green ceramic tapes and utilized for fabrication of multilayer ceramic capacitors using the LTCC technology. This material belongs to the group of high permittivity nonferroelectric compounds with a complex perovskite structure of CaCu₃Ti₄O₁₂, that causes the spontaneously formation of IBLCs.

A zero X‐Y shrinkage low temperature cofired ceramic (LTCC) substrate was developed, which was applied to flip‐chip bonded chip‐size packages (CSPs) and multichip modules (MCMs). The Ag internal conductor, the AgPd external conductor and the newly developed Ag via conductor could be used by matching the sintering shrinkage behaviour with that of the zero X‐Y shrinkage LTCC substrate. Flip‐chip bonding using the stud‐bump ‐bonding (SBB) technique could be performed on this substrate without Au plating on the external conductor. Stable flip‐chip bondability was obtained.

The paper aims to report on fabrication procedure and present microstructure and dielectric behavior of multilayer porous low-temperature cofired ceramic (LTCC) structures based on glass-cordierite and glass-alumina.

The LTCC structures were created as multi-layered composites with dense external layers and inner layers with intentionally introduced porosity. Two preparation methods were applied – subsequent casting of both kinds of slurries and conventional isostatic lamination of dried green tapes arranged in the designed order. Optical microscope observations were carried out to analyze the microstructure of green and fired multilayer structures and pore concentration. To evaluate the adhesion strength of the composite layers, pull test was performed. Dielectric behavior of the composites was studied in the frequency range 50 kHz-2 MHz.

The fabricated porous LTCC structures showed dielectric constant of 3-5.6. The lowest dielectric constant was attained for glass-cordierite composite made by the conventional tape casting/lamination/firing method from slurry with 50 per cent graphite content. The samples prepared using multiple casting were of worse quality than those fabricated in conventional process, contained irregular porosity, showed tendency for deformation and delamination and exhibited a higher dielectric constant.

Search for new low dielectric constant materials applicable in LTCC technology and new methods of their fabrication is an important task for development of modern microwave circuits.

This paper aims to fabricate and characterize ZnO-based multilayer varistors.

Tape casting technique was utilized for preparation of multilayer varistors based on ZnO doped with Pr, Bi, Sb, Co, Cr, Mn and Si oxides. Scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) methods were used to study the microstructure, elemental and phase compositions, respectively, of the varistors. Dielectric properties were investigated by impedance spectroscopy. Current–voltage (I–U) dependences were measured to characterize nonlinear behavior of the fabricated varistors.

XRD, SEM and EDS studies revealed dense microstructure of ceramic layers with ZnO grains sized 1-4 μm surrounded by nanometric Bi-rich films, submicrometer Zn₇Sb₂O₁₂ spinel grains and needle-shaped Pr₃SbO₇ crystallites. Praseodymium oxide was found to be very effective as an additive restricting the ZnO grain growth. I–U characteristics of the fabricated multilayer varistors were nonlinear, with the nonlinearity coefficients of 23-27 and 19-51 for the lower and higher Pr₂O₃ content, respectively. The breakdown voltages were 60-150 V, decreasing with increasing sintering temperature.

Low-temperature cofired ceramics technology enables attaining a significant progress in miniaturization of electronic passive components. Literature concerning application of this technology for multilayer varistors fabrication is limited. In the present work, the results of XRD, SEM and EDS studies along with the I–U and complex impedance dependences are analyzed to elucidate the origin of the observed varistor effect. The influence of sintering temperature and Pr₂O₃-doping level was investigated.