Towards a low‐power miniaturized micromechanical electronic nose

An electronic nose based on an array of vibrating doubly clamped beams is proposed. These very high aspect ratio (length/thickness) suspended resonators can be individually functionalized by applying polymer coatings by an inkjet printing approach. The absorption of volatile compounds induces a swelling of the polymers that results in axial stress formation and a shift of the resonance frequency. Furthermore, integrated piezoelectric transducers are used for both actuating the resonators, as well as monitoring their resonance frequency in an oscillator loop. This allows for detection at ppm-level concentrations of low-molecular weight volatiles.