Self-leveling uncooled microcantilever thermal detector

Bimaterial microcantilevers can be used as highly sensitive uncooled infrared (IR) detectors. Since the transduction efficiency of microcantilevers depends on their deflection, it is important to minimize cantilever deflections caused by factors other than IR radiation (e.g., intrinsic mechanical stresses and ambient temperature fluctuations). In this letter we report on a design of a microcantilever IR detector that is immune to ambient temperature changes and other sources of interfering mechanical stresses. We modeled and experimentally measured responses of such devices to IR radiation as well as to ambient temperature changes. Both modeling and experimental results indicate that the implemented innovative designs can combine excellent IR sensitivity with negligible sensitivity to the ambient temperature changes. (C) 2002 American Institute of Physics.