Resonating microbridge mass flow sensor

A resonating microbridge mass flow sensor with a frequency output is presented, based on standard IC and thin-film technologies, and on front-side anisotropic etching. The operation, realization, theory and experiments are described. The sensitivity is compared with that of a resonating membrane prototype. Preliminary results show a base resonance frequency of 85 kHz at a temperature elevation of the microbridge of 20 °C, with a shift of 0.8 kHz in the mass flow range from 0 to 10 sccm.