This paper presents design optimization, numerical modelling, fabrication and characterization of a single-axis comb drive MEMS gap-changeable differential capacitive accelerometer with a compact footprint of 2 mm × 2 mm. High sensitivity is achieved by optimizing the ratio of the anti-finger gap to finger gap spacing. It is found that a gap ratio of 3.44 leads to a displacement sensitivity of 0.0139 µm/g and a capacitive sensitivity of 80 fF/g. Finite element analysis is used to find the mode shape and frequency. Scanning electron microscope and capacitance-voltage measurements are employed to confirm the devices work. An enlarged static capacitance of 14.46 ± 0.42 pF is measured due to the enlarged stator anchor width. Electrical sensitivity of 35.93 mV/g is obtained by using the capacitance readout circuit at the system level, and the electrical sensitivity is practically constant over the frequency range of 100–200 Hz.

本文介绍了紧凑型占地2 mm×2 mm的单轴梳状驱动MEMS间隙可变差分电容加速度计的设计优化，数值建模，制造和特性。通过优化防指间隙与指间隙的比例，可以实现高灵敏度。发现间隙比为3.44导致位移灵敏度为0.0139μm/ g和电容灵敏度为80fF / g。使用有限元分析来找到模式形状和频率。使用扫描电子显微镜和电容电压测量来确认设备正常工作。由于定子锚固件宽度的增加，测得的静电电容为14.46±0.42 pF。通过在系统级使用电容读出电路，可获得35.93 mV / g的电灵敏度，