Abstract. Ion-selective electrodes (ISEs) have been proven particularly useful in water
analysis. They are usually used as single-rod measuring chains in different
designs, which are manufactured using precision mechanical manufacturing and
assembling technologies. The paper describes a microsystem technology approach
for the fabrication of miniaturized electrochemical sensors. The ceramic HTCC (high-temperature co-fired ceramic)
and LTCC (low-temperature co-fired ceramic) multilayer technology enables suitable processes for the
manufacturing of robust and miniaturized sensor arrays with a high functional
density. Design, manufacture, and electrochemical performance of the novel
ceramic multilayer-based sensor array are presented in the paper using various
examples. An adapted material and process development was carried out for the
sensitive functional films. Special thick-film pastes for the detection of the
pH value as well as NH4+, K+, Ca2+,
and Cu2+ ion concentrations in aqueous solutions were
developed. Ion-sensitive thick-film membranes were deposited on a ceramic
multilayer sensor platform by means of screen-printing. All ISEs, integrated
in the sensor array, showed suitable electrochemical performances including a
very quick response (several seconds) combined with a high sensitivity
(exhibiting Nernstian behaviour) in the tested measuring range. The obtained
sensitivities were around 57 mVper decade: for the pH sensor,
30 mVper decade for calcium, 53 mVper decade for potassium,
and 57 mVper decade for ammonium. Depending on the application,
different sensitive electrodes on the ceramic sensor array can be combined as
required.
Ceramic multilayer technology as a platform for miniaturized sensor arrays for water analysis
