一种高分辨率电容微加速度计的设计研究

Design of a high-resolution capacitive microaccelerometer

分析了影响加速度计分辨率的因素,在此基础上,通过采用深度反应离子刻蚀工艺获得大的敏感质量和小的电极间隙、采用电容变化量比枝齿梳状敏感结构大一倍的直齿梳状敏感结构和利用静电负刚度来降低结构的刚度等措施提高器件分辨率。最后给出了一种新的设计方案,叙述了其工作原理并分析了影响其闭环灵敏度的因素。

Some factors that affect the resolution of the accelerometer are analyzed.To improve the resolution ,some improvements have been adopted.Bigger sense mass and litter gap between the comb electrodes are obtained by DRIE process ,bigger capacitance change one time than straight comb finger type of capacitive sensing element is acquired by using branched comb finger type of capacitive sensing element.Structure stiffness is decreased by using electrostatic negative stiffness.Finally ,the operation principle of a new design is demonstrated ,analyzing the factor that affect the closed-loop sensitivity.