Design and TEM simulation of a MEMS based microcantilever cardiac marker sensor

Piezoresistive actuation of a microcantilever induced by biomolecular binding such as DNA hybridization and antibody-antigen binding is an important principle useful in biosensing applications. As the magnitude of the forces exerted is small, increasing the sensitivity of the microcantilever becomes critical. In this paper, we are considering to achieve this by geometric variation in the cantilever. The sensitivity of the cantilever was improved so that the device can sense the presence of antigen even if the magnitude of surface-stresses over the microcantilever was very small. We consider a "T-shaped" cantilever that eliminates the disadvantages while improving the sensitivity simultaneously. Simulations for validation have been performed using INTELLISUITE software (a micro-electromechanical system design and simulation package). The simulations reveal that the T-shaped microcantilever is almost as sensitive as a thin cantilever and has relatively very low buckling effect. Simulations also reveal that with an increase in thickness of the cantilever, there is a proportional decrease in the sensitivity. © 2010 by ASME.