Design Principle of Suspension of MEMS Gyroscope

Canceling and minimizing quadrature error is the key to improve the performance of MEMS gyroscopes. This paper addresses how to design suspension springs to decrease the quadrature error which induced with manufacture asymmetric. According to the stiffness matrix of suspension spring, the relationship among quadrature error, terms of stiffness matrix and width mismatch was put forward. The off-diagonal term which is coupled between driven and sensing directions has larger effect on the quadrature error than other off-diagonal terms of system stiffness matrix. The design principle of suspension springs of MEMS gyroscope was put forward, which is suggest that U-spring, serpentine spring and folded-flexure spring should be preferential adopted. At last, a z-axis MEMS gyroscope was improved based on the design principle, and the results of FEM simulation and experiment show the quadrature error is decreased largely