Signal-to-noise ratio of resonant microcantilever type chemical sensors as a function of resonant frequency and quality factor

Resonant microstructures can be used as chemical microsensors, by adding a sensitive coating to the device structure. Those vibrating structures are sensitive to the coating mass changes which modify the natural resonant frequency. The sensitivity, key parameter of such sensor, is proportional to the resonant frequency. But, if detection method consists in frequency measurement with an oscillator circuit, the noise signal must be taken into account. A large study of these reflections, combined with a signal-to-noise ratio optimization, leads us to maximize quality factor to microstructure thickness ratio.