Dickschicht-Feuchtesensor auf der Basis halbleitenden MnWO4-Metalloxids. Teil 1. Aufbau und Charakterisierung des Feuchtesensors

This paper describes the results of studies on fabrication and characterization of a novel thick-film ceramic humidity sensor with conductive properties. Semiconductive MnWO4 with a particle size of 3.0 mu m was used as the sensitive raw material which was screened into a 40 mu m polyceramic layer. Cations instead of a glass binder were added by mixing the humidity sensor paste. This new fabricating procedure ensures a rich porosity of the fired sensing layer and a good adhesion of the sensitive saver to the Al2O3 substrate. The sandwich configuration of the sensor element allows the sensitive layer to be used optimally. The developed thick-film humidity sensor shows a high sensitivity, fast responce and small hysteresis. The effect of the temperature on the sensor characteristics can be compensated by using of a thick- film NTC-resistor.