title: Potentiometric RuO2-Ta2O5 pH sensors fabricated using thick film and LTCC technologies.
abstract: The paper reports on the preparation, properties and application of potentiometric pH sensors with thick film RuO2-Ta2O5 sensing electrode and Ag/AgCl/KCl reference electrode screen printed on an alumina substrate. Furthermore, it presents fabrication procedure and characterization of a new miniaturized pH sensor on LTCC (low temperature cofired ceramics) substrate, destined for wireless monitoring. The crystal structure, phase and elemental composition, and microstructure of the films were investigated by X-ray diffractometry, Raman spectroscopy, scanning electron microscopy and energy dispersive spectroscopy. Potentiometric characterization was performed in a wide pH range of 2-12 for different storage conditions and pH loops. The advantages of the proposed thick film pH sensors are: (a) low cost and easy fabrication, (b) excellent sensitivity close to the Nernstian response (56mV/pH) in the wide pH range, (c) fast response, (d) long lifetime, (e) good reproducibility, (f) low hysteresis and drift effects, and (g) low cross-sensitivity towards Li(+), Na(+) and K(+) as interfering ions. The applicability of the sensors for pH measurement of river, tap and distilled water, and some drinks was also tested.
authors.affiliation: Institute of Electron Technology, Krakow Division, 30-701 Kraków, Zabłocie 39, Poland.
authors.forename: Libu
authors.initials: L
authors.lastname: Manjakkal
authors.affiliation: Institute of Electron Technology, Krakow Division, 30-701 Kraków, Zabłocie 39, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Zaraska
authors.affiliation: Institute of Electron Technology, Krakow Division, 30-701 Kraków, Zabłocie 39, Poland.
authors.forename: Katarina
authors.initials: K
authors.lastname: Cvejin
authors.affiliation: Institute of Electron Technology, Krakow Division, 30-701 Kraków, Zabłocie 39, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Kulawik
authors.affiliation: Institute of Electron Technology, Krakow Division, 30-701 Kraków, Zabłocie 39, Poland. Electronic address: dszwagi@ite.waw.pl.
authors.forename: Dorota
authors.initials: D
authors.lastname: Szwagierczak
keywords: Hysteresis effect; LTCC; Potentiometric analysis; RuO(2)–Ta(2)O(5); Thick film; pH sensor