一种硅梁谐振加速度计结构设计与模拟分析

Design and Simulation of a Silicon Beam Resonant Accelerometer

为了提高谐振加速度计的灵敏度以及稳定性,提出一种基于微杠杆力学放大机构的硅梁谐振式加速度计结构,并对其进行了有限元模拟分析。该加速度计由两个静电激励电容检测的硅谐振梁组成差分输出,采用硅深刻蚀以及硅玻璃阳极键合等体硅工艺制作。模拟结果表明新结构提高了加速度计灵敏度,有效改善了交叉灵敏度、线性度、温度稳定性等。

In order to enhance sensitivity and stability of resonant silicon accelerometers, a novel differential design based on effective micro leverage structures was proposed and some numerical modeling results for this scheme were presented. The accelerometer contained two vibrating beams excited electrostatically and sensed capacitively. In-plane acceleration was then measured by working out the difference of the two resonant frequencies. The device was fabricated by means of MEMS bulk-silicon technology, including ICP deep etching and Si-glass bonding. Simulation results show that the novel structure increases the scale factor of the resonant accelerometer, and ameliorates other performance such as cross axis sensitivity of insensitive input accelera- tion, linearity, temperature stability, etc.