A CMOS-compatible, magnetically actuated resonator for mass sensing applications

The characterization of a microresonator fabricated in a standard, CMOS-compatible technology, is presented. The device is a silicon dioxide plate, suspended to two torsional springs. A first metal loop integrated on the plate, in conjunction with an external magnet, is used to drive the plate into mechanical resonance, while a second loop is used for detection. The resonator can be used as an integrated microbalance: a shift of its resonance frequency can be related to the adsorption, on the preventively functionalised plate, of a specific chemical or biochemical species. The performances of the device as a resonator, i.e. its resonance frequency, quality factor and its frequency response were extracted both with optical and electrical methods.