Behavioral Modeling of a CMOS Compatible High Precision MEMS Based Electron Tunneling Accelerometer

Abstract

The paper presents a comprehensive behavioral model of a high precision tunneling accelerometer. Design and optimization of the silicon based tunneling has also been reported in this work. The accelerometer is CMOS compatible and has actuation voltage within CMOS bias levels. The proposed structure uniquely combines the electron tunneling based sensing and capacitive actuation. A feedback controller is designed to measure the acceleration under constant gap mode of operation. The full dynamic range of operation is 1 mug to 200 mug with a resolution in the order of nano-g. The cross-axis sensitivity is less than 1% and the shock survivability is 10 g for a 10 ms shock with 0.1 ms rise time. The Brownian noise floor of the system has also been studied and the squeeze film damping effects on the system has been shown.