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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 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.

The paper presents the application of two advanced thick‐film techniques: etching of fired thick‐films and photoimaging of photosensitive thick‐films for fabrication bandpass microwave filters operating in the frequency range from 6 to 14 GHz. Modified screen printing through ultra‐thin calendered screens is used for comparative goals. Advanced techniques are combined with novel thick‐film conductors including photosensitive pastes and etchable pastes.