A Fully Symmetric and Completely Decoupled MEMS-SOI Gyroscope

This paper introduces a novel MEMS gyroscope that is capable of exciting the drive mode differentially. The structure also decouples the drive and sense modes via an intermediate mass and decoupling beams. Both drive and sense modes are fully differential enabling control over the zero-rate-output for the former and maximizing output sensitivity using a bridge circuit for the latter. Further, the structure is fully symmetric about the x- and y- axes which results in minimizing the temperature sensitivity problem. Complete analytical analysis based on the equations of motion was performed and verified using two commercially available finite element software packages. Results from both methods are in good agreement. The analysis of the sensor shows an electrical sensitivity of 1.14 (mV/(°/s)). The gyroscope was fabricated using single mask and deep reactive ion etching. The measurement of the resonance frequency performed showing a good agreement with the analytical and numerical analysis. [PUBLICATION ABSTRACT]