An improved structural design for accelerometers based on slotted eight-beam structure

Purpose - The purpose of this paper is proposed a new structure design for high performance accelerometer. Design/methodology/approach - An improved sensitivity structure considering sensitivity, natural frequency and cross-axis sensitivity is established and realized. The proposed structure was designed to improve the trade-off between the sensitivity and the natural frequency of piezoresistive accelerometer and eliminate the lateral sensitivity effect by the specific configuration, which is made possible by incorporating slots into the eight-beam structure. The mechanical model and its mathematical solution are established for calculating the sensitivity and natural frequency behavior of the designed structure. The developed sensor is fabricated on the n-type single-crystal silicon wafer and packaged for experiment. The accelerometer prototype was tested in the centrifugal machine and dynamic calibration system. Findings - The experimental results show that the sensitivity of the designed sensor is 0.213 mV/(Vg) and the natural frequency of the sensor is 14.22 kHz. Compared with some piezoresistive accelerometers in literatures, the designed sensor possesses a suitable characteristic in sensitivity, natural frequency and transverse effect, which allows its usage in measuring high frequency vibration signals. Originality/value - The accelerometer with slotted eight-beam structure shows a good performance in the static and dynamic experiments and can be used in measuring high frequency vibration signals.