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This paper aims to present systematic studies of a wide spectrum of geometrical and electrical properties of thick‐film and LTCC microresistors (with designed dimensions between 50 × 50 μm² and 800 × 200 μm²).

The geometrical parameters (average length, width and thickness, relations between designed and real dimensions, distribution of planar dimensions) are correlated with basic electrical properties of resistors (sheet resistance and its distribution, hot temperature coefficient of resistance and its distribution distribution) as well as long term thermal stability and durability of microresistors to short electrical pulses.

Fodel process gives better resolution than standard screen‐printing and leads to smaller dimensions than designed, smaller absolute error and better uniformity of planar sizes. Microresistors made in full Fodel process show much weaker dimensional effect and exhibit noticeably smaller distribution of basic electrical properties.

Presents systematic studies of a wide spectrum of geometrical and electrical properties of thick‐film and LTCC microresistors.

Aims to evaluate different thick‐film materials for use in strain sensors and temperature sensors on low‐temperature co‐fired ceramic (LTCC) substrates.

LTCC materials are sintered at the low temperatures typically used for thick‐film processing, i.e. around 850°C, The thick‐film resistor materials for use as strain and temperature sensors on LTCC tapes are studied. Thick‐film piezo‐resistors in the form of strain‐gauges are realised with 10 kΩ/sq. 2041 (Du Pont)and 3414‐B (ESL), resistor materials; thick‐film temperature‐dependent resistors were made from PTC 5093 (Du Pont), and NTC‐4993 (EMCA Remex) resistor materials.

The X‐ray spectra of the 2041 and 3414‐Bb low TCR resistors after drying at 150°C and after firing display more or less the same peaks. The electrical characteristics of 2041 resistors fired on alumina and LTCC substrates are similar indicating that the resistors are compatible with the LTCC material. After firing on LTCC substrates the sheet resistivities and TCRs of the 3414‐B resistors increased. Also, there is a significant increase in the GFs from 13 to over 25.

Investigates the compatibility of thick‐film materials and the characteristics of the force and temperature sensors.

The purpose of this paper is to present the results of thermal analysis of cermet resistors made on alumina or LTCC substrate and polymer thick-film resistors embedded in FR-4 substrate.

The study was performed using a thermal imaging method. The research was carried out with an additional consideration of such factors as sheet resistance (which depended on the type of resistive paste), the size and topology of element and the kind of contact material (Cu, Ag or Ni/Au). A few key points on the element were specified for which a more thorough analysis was carried out. The results were approximated by physically acceptable function which allowed to determine the influence of different mechanisms of heat transfer and determine their time and thermal constants.

The effectiveness of heat dissipation from resistor is determined by the type of substrate material, width of conductive paths, and contact material. The best results were observed for elements with wider conductive paths made of Cu or Ni/Au. The LTCC substrate ensures the fastest achieving of stable temperature on the component. The changes of the temperature gradient in time can be described by a formula consisting of two or three exponent parts, each one presenting different mechanism of change.

These studies do not include more detailed determination of nature of found mechanisms of change. There has not also been established what form of the formula is more accurate physically description of the results for respective structure.

The results provide important data of the thermal properties of the chosen materials. This allows to determine their usability for specific applications where heat distribution plays an important role. The used analysis method is proven to provide reliable results and can be considered to be used for further studies in that subject.

The resolution of conventional graphical gravures is limited to about 50 to 100 microns depending on the technology used. For these gravures the depths are dependent on the widths of the grooves. For electrical circuitry, the target is to achieve 25 microns line and space widths in the near future. To obtain a reasonably high sheet resistance, the printed ink height must be reasonably high. The stated requirements require further development of the whole printing process together with the associated inks. The first step was to evaluate the gravure manufacturing method, which is capable of producing gravures of sufficient accuracy and uniform depth. In this paper a new gravure printing plate manufacturing method with high accuracy is presented. Printing results made with the manufactured gravure and tailored inks are reported.

The purpose of this paper is to focus on a description of reliable bonding technique of zero-shrink low-temperature co-fired ceramic (LTCC) and alumina ceramics. LTCC is widely used for manufacturing electrical systems in 3D configuration. LTCC substrates were so far bonded with alumina ceramics using additional adhesive layers with subsequent firing or curing cycle. With the advent of the zero-shrink LTCC substrates, it is now possible to bond unfired substrates with other fired substrates, for example fired LTCC or alumina substrates. Alumina substrate in combination with LTCC brings advantages of good thermal conductivity for usage in heating elements or packaging.

The test structure contains a thick-film pattern for verification of the compatibility of the bonding process. We have used two methods for bonding the substrates: cold chemical lamination (CCL) and thermo compression method, using a dielectric thick-film paste as the adhesive. Optical microscopy, scanning electron microscopy and electric testing of the screen-printed patterns were used for verification of the bonding quality.

The thermo-compression method gave poor results in comparison with the CCL method. The best quality of lamination was achieved at room temperature combined with low pressure for both types of bonding materials. In addition, a possibility of using this bonding method for sensor fabrication was investigated. The ceramic pressure sensor samples with a cavity were created.

The possibility of bonding two different ceramic materials was investigated. A new approach to ceramic bonding showed promising results with possible use in sensors.

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.

This paper presents possibility of laser application for fabrication of 3D elements and structures. The Aurel NAVS‐30 Laser Trimming and Cutting System with special software was used. It was applied successfully for fabrication of vias (minimum diameter – 50 μm) in fired and unfired LTCC ceramics and channels with width between 100 μm and 5 mm. The achievements and problems are presented and discussed. The influence of lamination process on quality of vias and channels as well as the problems connected with interaction of laser beam with ceramic tapes are shown. Three‐dimensional resistors and microfluidic system were successfully designed and fabricated based on our investigations. Chosen electrical and thermal parameters of constructed devices are shown, too.

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.

The purpose of this study was to design, fabricate and test devices based on transformers integrated with low-temperature co-fired ceramic (LTCC) modules with isolation between primary and secondary windings at the level between 6 and 12 kV.

Insulating properties of the LTCC were examined. Dielectric strength and volume resistivity were determined for common LTCC tapes: 951 (DuPont), 41020, 41060 (ESL), A6M (Ferro) and SK47 (KEKO). According to the determined properties, three different devices were designed, fabricated and tested: a compact DC/DC converter, a galvanic separator for serial digital bus and a transformer for high-voltage generator.

Breakdown field intensity higher than 40 kV/mm was obtained for the test samples set, whereas the best breakdown field intensity of about 90 kV/mm was obtained for 951 tape. The materials 41020 and 951 exhibited the highest volume resistivity. Fabricated devices exhibited safe operation up to a potential difference of 10 kV, limited by minimum clearance. Long-term stability was assured by over 20 kV strength of inner dielectric.

This paper contains description of three devices made in the LTCC technology for application in systems with high-voltage isolation requirement, for example, for power or railway power networks.

The results show that LTCC is a suitable material for fabrication of high-voltage devices with integrated passives. Technology and properties of three examples of such devices are described, demonstrating the ability of the LTCC technology for application in reliable high-voltage devices and systems.

This paper aims to present the possibility of computer-aided technology of chemical metallization for the production of electrodes and resistors based on Ni-P and Ni-Cu-P layers.

Based on the calculated parameters of the process, test structures were made on an alumina substrate using the selective metallization method. Dependences of the surface resistance on the metallization time were made. These dependencies take into account the comparison of the calculations with the performed experiment.

The author created a convenient and easy-to-use tool for calculating basic Ni-P and Ni-Cu-P layer parameters, namely, surface resistance and temperature coefficient of resistance (TCR) of test resistor, based on chemical metallization parameters. The values are calculated for a given level of surface resistance of Ni-P and Ni-Cu-P layer and defined required range of changes of TCR of test resistor. The calculations are possible for surface resistance values in the range of 0.4 Ohm/square ÷ 2.5 Ohm/square. As a result of the experiment, surface resistances were obtained that practically coincide with the calculations made with the use of the program created by the authors. The quality of the structures made is very good.

To the best of the authors’ knowledge, the paper presents a new, unpublished method of manufacturing electrodes (resistors) on silicon, Al₂O₃ and low temperature co-fired ceramic substrates based on the authors developed computer program.