一种电容式高量程微机械加速度计的设计分析

针对特殊场合的高g值加速度测试需求，提出了一种叉齿电容式高量程微机械加速度计的结构形式，采用面内敏感的变面积差动电容变化方式，并针对传感器固有频率、横向效应、量程和加速度灵敏度进行了设计分析。仿真结果表明：该加速度计量程200 000 g，固有频率266.2 kHz，模态分离比大于2.5，0~10 kHz通频带内加速度分辨率优于60 g. 基于硅-玻璃微机械工艺进行了加速度计微结构的流片加工、镜检测试和传感器的初步冲击实验验证。相比已有的高量程微机械加速度计，该设计具有线性度好、横向效应小、加速度灵敏度高和抗高过载能力强等特点。

Design and Analysis of a High-g Capacitive Micro-machined Accelerometer

A kind of high-g capacitive micro-machined accelerometer with comb structure is proposed for the special demand of high-g acceleration test. It is an in-plane sensitive accelerometer with area-variable differential capacitance. The natural frequency, transverse effect, measuring range and acceleration sensitivity of sensor are designed and analyzed. Simulation results show that, the measuring range of the designed accelerometer is 200 000 g with the acceleration resolution of better than 60 g in 0-10 kHz bandwidth; its natural frequency is 266.2 kHz , and the modal separation ratio is more than 2.5. It is fabricated by silicon-on-glass MEMS technology. The test and the primary shock experiment of sensor are performed. Compared with the existing high-g micro-machined accelerometers, the designed accelerometer has good linearity, small transverse effect, high acceleration sensitivity and strong ability to resist high overload.