NTC temperature sensor and process for producing NTC temperature sensing elements

摘要

The NTC temperature sensor includes a NTC temperature sensing element having an NTC resistor and made of a laminated composite of ceramic films, which is so designed that the ambient air or oxygen supplied by electrolytic pumping has free access, via a channel in the laminated composite, to the NTC resistor. The NTC resistor is hermetically sealed from a gas being measured. Solid electrolyte films which conduct O.sup.-2 ions, and films based on Al.sub.2 O.sub.3 can be used to make the laminated composite. The NTC resistor characteristic curve is independent of the composition of the gas being measured. The laminated composite can be formed of at least three solid electrolyte ceramic films including a base film provided with punched-out interconnection holes and conductor tracks printed by thick film technology, an intermediate film having a punched-out channel and a channel enlargement around the ends of the conductor tracks forming the electrodes of the NTC resistor, and a covering film.