Sensor based on arrays of sub-micrometer scale resonant silicon cantilevers integrated monolithically with CMOS circuitry

A mass sensor, based on arrays of cantilevers for multiple detection, is presented. Excitation and readout is performed electrostatically. Polysilicon cantilevers are integrated monolithically with CMOS in a compatible process. Integration of arrays of cantilever allows performing multiple detections on the same device. A multiplexing system to select individual cantilevers is implemented as well as a scheme based on two readout circuits for differential measurements. A mass resolution of 5/spl middot/10/sup -18/ g has been achieved in the first working devices.