Miniaturized pressure sensor

摘要

An entirely surface micromachined free hanging strain-gauge pressure sensor is disclosed. The sensing element consists of a 80 mum long H-shaped double ended supported force transducing beam (16). The beam is located beneath and at one end attached to a square polysilicon diaphragm (14) and at the other end to the cavity edge. The sensor according to the invention enables a combination of high pressure sensitivity and miniature chip size as well as good environmental isolation. The pressure sensitivity for the sensor with a H-shaped force transducing beam, 0.4 mum thick was found to be 5 muV/V/mmHg.