Development of surface micromachinable capacitive accelerometer using fringe electrical field

This paper demonstrates a new type accelerometer, which consists of a dielectric seismic mass and comb-shaped planar capacitor underneath it. The simple structure of the device allows using polymer Parylene as the proof mass, so the technology is greatly simplified and only surface micromachining is required. Measuring principle is detecting capacitance change according to the dielectric mass movement in the fringe electrical field. This principle is verified by FEM simulation. Prototype accelerometers are fabricated and calibrated with the aid of off-chip capacitive readout IC.