Design of Silicon Resonant Micro Accelerometer Based on Electrostatic Rigidity

摘要

The structure characteristics and working principle of silicon resonant micro-accelerometer based on electrostatic rigidity are presented. Dynamic characteristics of double-ended tuning fork (DETF) in the sensor are analyzed. Force equilibrium equations of mass and DETF are built respectively for with or without acceleration, through which the relationship between DETF resonant frequency and acceleration is obtained. The influences of folded supporting beams linked with proof mass and gap between capacitive parallel plates on the sensor sensitivity are analyzed, and finally a resonant micro accelerometer with sensitivity of 60 Hz/g is designed and fabricated with bulk-silicon dissolved processes.