Health & Environmental Research Online (HERO)


Print Feedback Export to File
2848793 
Journal Article 
Some practical points to consider with respect to thermal conductivity and electrical resistivity of ceramic substrates for high-temperature gas sensors 
Kita, J; Engelbrecht, A; Schubert, F; Gross, A; Rettig, F; Moos, R 
2015 
1 
Sensors and Actuators B: Chemical
ISSN: 0925-4005
EISSN: 1873-3077 
213 
541-546 
WOS:000352152500069 
In the field of gas sensors and high temperature flow sensors, ceramic thick-film-based structures play a key role, particularly in harsh environments. Their substrates have to be electrically insulating and chemically inert. Ceramic substrates, especially alumina ones, are often considered as ideal sensor substrates. However, neither their electrical resistivity nor their chemical inertness is ideal. Even the thermal conductivity is that temperature dependent that one has to consider it when modeling temperature profiles. In this contribution, measurements on the resistivity and the thermal conductivity between room temperature and 800 degrees C of two related materials used for gas sensors substrates - alumina and LTCC ceramics - are presented. Additionally, resistance data of uncoated interdigital structures when exposed to NO2 at around 300 degrees C indicate that reactions between substrate and NO2 may occur and have to be kept in mind. (C) 2015 Elsevier B.V. All rights reserved. 
Ceramic substrates; Alumina; LTCC; Gas sensors; Electrical resistivity; Thermal conductivity; NO2 sensor