Design optimization of three-axis accelerometers based on four seismic masses

This paper presents analytical models for three axis accelerometers based on four seismic masses. The models make it possible to better understand and to predict the behavior of these micro-accelerometers. Cross-axis sensitivity, resolution, frequency response and direction dependence are investigated for a variety of sensing element structures and readout methods. With the maximum sensitivity direction of the individual sensing elements inclined 35.3° with respect to the chip surface the properties becomes direction independent, i.e. identical resolution and frequency response in all directions.