Characterisation of the electrical response of a novel dual element thermistor for low frequency applications

Abstract

This work is aimed at characterising the DC electrical response of a temperature sensitive microbolometer device. The contribution lies with the choice and the structure of the device, a novel bolometer infrared sensing structure consisting of dual sensing elements that are thermally very closely coupled on a single membrane supporting structure. A mathematical model is presented to characterise the behaviour of the device resistance and conductance for a given biasing current. A modified experiment of a well published non-optical method exploiting the normally unwanted Joule heating of a device when biased with a large direct current is employed for the experimental verification and validation of the theoretical model. The measured results indicate that the proposed model approximates the measured results well. Although some deviation occurs, this is to be expected and discussed.