Design and simulation of a MEMS Fabry-Perot accelerometer with ultra-low cross-axis sensitivity

Cross-axis sensitivity is important as same as resolution and sensitivity for accelerometer especially in the high precision application field, such as crustal movement, earthquake monitoring, and mineral exploration. This paper proposed a MEMS Fabry-Perot accelerometer with ultra-low cross-axis sensitivity. The origin of the cross-axis sensitivity for the proposed accelerometer was analyzed. To reduce the cross-axis sensitivity, a novel separated mass-spring structure whose proof mass includes four anti-roll masses and a sensing mass was designed, the anti-roll masses can isolate the x and y direction acceleration from being transmitted to the central sensing mass, and the mechanism was studied and verified through theoretical and simulation technology. The performance of the accelerometer was evaluated by simulation, and the results indicated that the bandwidth, spring stiffness, sensitivity, and cross-axis sensitivities are 45.16 Hz, 35.4 N m-1, 15.789 μm g-1, 0.0041% (x/z axis) and 0.0045% (y/z axis), respectively.