A novel capacitive absolute pressure sensor using SON technology

A novel capacitive absolute pressure sensor is fabricated and evaluated in this paper. The pressure sensitive membrane is formed by SON (Silicon on Nothing) technology [1], and a glass chip with Au/Ti electrodes is bonded on the membrane opposite by anodic bonding technique at 400°C to detect the pressure change. Compared to the existing capacitive absolute pressure sensors, the hermetical sealing process is not required, high vacuum cavity can be easily formed, an excellent long-term stability can be achieved, and detection circuitry can be easily integrated with the sensor.