Low Temperature Co-fired Ceramics Processing Parameters Governing the Performance of Miniaturized Force Sensors

For the development of miniaturized force sensors, built up in ceramics technology with piezo-resistive principle, the compatibility of the piezo-resistive thick-film paste with the substrate and termination paste has to be verified. This paper deals with the compatibility of the ESL 3414-A piezo-resistive paste on HTCC (high temperature co-fired ceramics) substrates (alumina as reference and the partially stabilized zirconia tape ESL 42013-A) as well as on LTCC (low temperature co-fired ceramics) substrates (Heraeus AHT01-005, AHT08-047, CT707; and CeramTec GC) under different manufacturing conditions. The sheet resistance at room temperature, the longitudinal gauge factor at room temperature and the temperature coefficient of resistance have been measured. The results are compared with microscope images showing cracks in distinct cases. Finally, the compatibility and thus applicability of the ESL 3414-A on the investigated substrates is evaluated.

Thin Resistive Thick-Film Layers Based on Precious Metal Resinate/Glass Systems

This paper describes the preparation and results obtained with a ruthenium-resinate/glass resistive system prepared by firing on to a 96% alumina substrate. The results have been compared with a gold/rhodium-resinate/glass system. It is found in the ruthenium system that the particle size is about 200 Å and because of this, conduction occurs at a very low volume percent conduction phase. Temperature Coefficient of Resistance behaviour of the ruthenium based system is still anomalous.