SiN beam resonant pressure sensors with a novel structure

In this paper, a resonant pressure sensor has been designed and fabricated by MEMS technology which consists of a silicon nitride beam supported by a single crystal silicon frame of a special design, mounting on a silicon diaphragm by bonding. The beam is electrothermally excited and its vibrations are detected by thin film piezoresistors. Numerical modeling is performed on design of diaphragm geometry and sensitivity of pressure measurement. Both computer simulation and experimental results show that the novel structure largely increases the pressure sensitivity.