A High-g Triaxial Piezoresistive Accelerometer with Sensing Beams in Pure Axial Deformation

We put forward a novel structure of three-axis high-g piezoresisitive accelerometer with pure axial deformation sensitive beams, which greatly improves the performance of accelerometer. The accelerometer's measurement range is 100,000 g. The advantages of novel structure are as follows. Firstly, the separation of sensor support structure and sensitive structure greatly weakens the coupling relationship between natural frequency and sensitivity. Secondly, the sensitive beam is always in a purely axially deformed state, to make full use of the deformation energy of sensitive beam, that greatly improves the measuring sensitivity of accelerometer. Then we simulated the main performance parameters of proposed accelerometer and optimized the structural parameters of novel structure. The measuring sensitivity of proposed accelerometer is simulated with the value of 1.2 μV/g/3V, and its resonant frequency is greater than 1 MHz. Finally, the fabrication process is designed for the accelerometer chip.