Integrated torsional-microbalance device in MEMS technology and fabrication process thereof

A system comprising:

• an interface;
• a microbalance that includes:
• a semiconductor substrate having a cavity;
• and
• a resonator suspended above the cavity of the substrate and including:
• a mobile body;
• a first arm coupled between the substrate and the mobile body, having a first thickness, and configured to enable oscillations of the mobile body with respect to the substrate;
• an actuation transducer coupled to the mobile body and configured to generate said oscillations at a resonance frequency;
• and
• a detection transducer configured to detect a variation in the resonance frequency,
• wherein the mobile body comprises a thin portion having a second thickness smaller than said first thickness of the first arm;
• a magnetic field generator coupled to the actuation transducer and to the detection transducer and configured to generate a magnetic field;
• a signal generator coupled to the actuation transducer, and configured to generate a signal to control the microbalance;
• and
• a processing unit, configured to process an output signal of the detection transducer.

A process, comprising:

• forming a MEMS microbalance, the forming including:
• forming a semiconductor substrate having a cavity;
• forming a resonator suspended above the cavity of the substrate and including:
• forming a mobile body;
• forming a first arm coupled between the substrate and the body, having a first thickness and configured to enable oscillations of the mobile body with respect to the substrate;
• forming an actuation transducer coupled to the body and configured to generate said oscillations at a resonance frequency;
• and
• forming a detection transducer configured to detect a variation of the resonance frequency,
• wherein forming the body comprises forming a thin portion having a second thickness smaller than said first thickness of the first arm.