Abstract:
Thermistors fit into the category of infra-red detectors commonly called thermal detectors which operate through the heating effects of the incident radiation. This thermal detector converts the infra-red radiation into an electrical signal and the basic property defining the performance in the ratio of electrical output to the incident energy on the sensitive area of the detector called the resonsitivity. The radiation used may either monochromatic or black body from a source at a specified temperature. This paper deals with the study of infrared properties of 'lead free' thick film NTC thermo-resistive sensor based on the mixture of spinel material and RuO2. Thick film thermistor was characterized using the basic physical techniques such XRD and SEM; XRD confirmed the formation of spinel phases whereas SEM showed the denser and smoother film surface. The thermo sensor showed exponential decrease in the resistance with respect to increase in temperature, very good responsivity (28.79/mW), repeatability and, the reproducibility.