Cantilever beam accelerometer based on surface micromachining technology

A concept involving an accelerometer made completely with surface micromachining technology is introduced. The sensor makes use of an effect based on electostatic force. Since only small surfaces are required, it is possible to keep the design relatively simple. In contrast to the capacitive principle, a so called critical voltage is measured which describes the transition from the stable to an unstable state of the system and depends on the effective acceleration. Preliminary tests and calculations indicate high sensitivity between 0.6 mV g^-1 and 100 mV g^-1 (unamplified) for structure with lengths between 120 mu m and 500 mu m.