Modeling and performance of uncoated microcantilever-based chemical sensors

Chemical sensors based on vibrating silicon microcantilevers without sensitive coating are investigated herein. The sensor signal is the relative variation of the microcantilever resonant frequency which depends on both the viscosity and the density of the fluid surrounding the microcantilever. This principle has been applied to the detection of binary gas mixtures. Experimental data for He/N2 and CO2/N2 environments are presented and compared to results of theoretical modeling. The advantages of such a gas sensor based on changes of physical properties are discussed (response time, sensitivity, selectivity, stability).