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Microwave and thermal problems in manufacturing high‐power microwave attenuators are considered and some proposals of thick film solutions are presented. Theoretical considerations have been confronted with the results of measurements.

‘Soldering and Cleaning in Electronics’ international conference, including an exposition, took place in Brno on 12–13 October 1993. The conference was organised by SMT‐Info, together with the ISHM‐Czech and Slovak Chapter. The purpose of this common action was to bring together the professionals in surface mount technology and thick film technology. In the framework of the conference, in which 130 home and foreign delegates participated, the annual meeting of the ISHM‐Czech and Slovak Chapter took place.

Low temperature co-fired ceramics (LTCC) technology-based micro-hotplates are of immense interest owing to their ruggedness, high temperature stability and reliability. The purpose of this paper is to study the role of thermal mass of LTCC-based micro-hotplates on the power consumption and temperature for gas-sensing applications.

The LTCC micro-hotplates with different thicknesses are designed and fabricated. The role of thermal mass on power consumption and temperature of these hotplates are simulated and experimentally studied. Also, a comparison study on the performance of LTCC and alumina-based hotplates of equivalent thickness is done. A thick film-sensing layer of tin oxide is coated on LTCC micro-hotplate and demonstrated for the sensing of commercial liquefied petroleum gas.

It is found from both simulation and experimental studies that the power consumption of LTCC hotplates was decreasing with the decrease in thermal mass to attain the same temperature. Also, the LTCC hotplates are less power-consuming than alumina-based one, owing to their superior thermal characteristics (low thermal conductivity, 3.3 W/ [m-K]).

This study will be beneficial for designing hotplates based on LTCC technology with low power consumption and better stability for gas-sensing applications.

A characteristic feature of LTCC is good workability. In some cases a LTCC‐based microsystem can be a good alternative to microsystems made in silicon or other technologies. Reasons for choosing LTCC‐Technology may be financial considerations or specific material properties. A main problem is to simplify a mechanical component in such a way, that it is possible to integrate this component in a planar structure with a small height in consideration of the restrictions of the LTCC‐Technology. In contrast to LTCC‐based substrates with only electrical circuits the integration of mechanical components make other demands on the different technological steps of the LTCC‐Process. In this paper some 3D‐structures made in LTCC‐like fluidic channels, membranes usable for micropumps or pressure sensors – and some aspects of required special technological demands are described.

Thermal properties of Pt or RuO₂ thick‐film heaters made on alumina, aluminum nitride or low temperature co‐fired ceramics (LTCC) were compared in the first step of our work. Special holes to improve the heat distribution were included. Several heater layouts were analysed. The heat distribution was measured by an infrared camera, at different heating power. Second, the optimization of LTCC constructions was carried out. The simple structure of LTCC permitted the achievement of a high package density. It was possible to integrate a heating element made from special thick‐film ink as a buried film, inside a substrate. An important step in our technology was the making of the holes. A pattern of holes (achieved by punching or laser cutting) around the heating area permitted a changeable heat gradient. The quality of lamination and the structure of the buried elements were investigated with an ultrasonic microscope.

A recent meeting involved co‐operation with the organisers of the Canadian High Technology Show and the local Chapter of the SMTA. The programme included an inspiring keynote address by Mr Frank J. Pipp, Xerox Corporation. The topic of the address was ‘Malcolm Baldridge National Quality Control and the Evaluation of Total Quality Control in Xerox Corporation.’

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.

ISHM‐Benelux has recently set up a permanent secretariat at the following address: