Laminated 3D structures made using lowtemperature co-fired ceramic (LTCC) technology are practical for ceramic micro-electro-mechanical systems (C-MEMS). The sensors for mechanical quantities, and/or actuators, are fundamental parts of MEMS. Thick-film resistors can be used to sense the mechanical deformations, and thick-film piezoelectric materials can be used as electro-mechanical transducers in a C-MEMS structure. The integration of these thick-film materials on LTCC substrates is in some cases difficult to realise due to interactions with the rather glassy LTCC substrates. The subject of our work is an investigation of thick-film materials for electro-mechanical transducers (sensors and actuators) and their compatibility with LTCC substrates. Resistors made with commercial thick-film resistor materials for use as sensors on LTCC substrates have been investigated and evaluated. Ferroelectric ceramic materials based on solid solutions of lead zirconate titanate (PZT) with low firing temperatures around 850°C were developed for thick-film technology and evaluated on LTCC substrates.

Pressure‐sensor miniaturization requires high‐density packaging. This means that designers are constantly faced with all kinds of challenging, and sometimes impossible, requirements. In this paper we will present three examples with specific technologies and aspects of miniaturization and packaging. The first example is a pressure switch, the second a pressure sensor and the third a smart pressure sensor.

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This paper presents the design of a wireless pressure-monitoring system for harsh-environment applications. Two types of ceramic pressure sensors made with a low-temperature cofired ceramic (LTCC) were considered. The first type is a piezoresistive strain gauge pressure sensor. The second type is a capacitive pressure sensor, which is based on changes of the capacitance values between two electrodes: one electrode is fixed and the other is movable under an applied pressure. The design was primarily focused on low power consumption. Reliable operation in the presence of disturbances, like electromagnetic interference, parasitic capacitances, etc., proved to be contradictory constraints. A piezoresistive ceramic pressure sensor with a high bridge impedance was chosen for use in a wireless pressure-monitoring system and an acceptable solution using energy-harvesting techniques has been achieved. The described solution allows for the integration of a sensor element with an energy harvester that has a printed thick-film battery and complete electronics in a single substrate packaged inside a compact housing.

Silicon piezoresistive pressure sensor dies are mounted on a ceramic substrate where the signal conditioning electronics are implemented in thick film technology. In this paper some of these techniques, e.g. special attachment and bonding requirements, methods for temperature compensation, the principles of parameter adjustment, and encapsulation, are presented. For illustration two examples are described. The first is a multipoint monitoring system with 720 measuring points in a test mattress. The second example is a family of industrial pressure transducers.

The eastern distribution limit of Spiraea decumbens s. str. is in Breginjski Kot (northwestern Slovenia), where we recorded 49 localities of this eastern-Alpine endemic plant species. We determined two new localities in a new quadrant (9746/4) on riparian rocks of the Nadiža River under Mt. Mija at Kozja Peč, which is currently the southeasternmost point of its entire distribution area. We conducted a phytosociological survey of 26 localities. This endemic occurs in dolomite rock crevices in stands classified within the association Spiraeo-Potentilletum caulescentis. On dolomite screes and torrential fens it is found to dominate on small areas in the successional stages, classified into the provisional association Aquilegio einseleanea-Spiraeetum decumbentis (alliance Petasition paradoxi) and into the new association Spiraeo decumbentis-Seslerietum calcariae (alliance Caricion austroalpinae). These stages are gradually becoming overgrown with thermophilous deciduous trees, and in one of the relevés we found the studied species in an open hop hornbeam stand classified into the association Fraxino orni-Ostryetum. Its populations are vital and unthreatened, except in the two new localities under Mt. Mija, which call for special protection due to their small size and a possibility of being backfilled with gravel.

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