A lateral-axis MEMS tuning fork gyroscope with nozzle-optimized squeeze-film sensing element

This paper presents a lateral-axis MEMS tuning-fork gyroscope with nozzle-optimized squeeze-film sensing element fabricated using silicon-on-glass process. The proposed nozzle-optimized sensing element is able to provide large capacitive output which is beneficial for mode-splitting design, while it is also compatible with standard 3-masks silicon-on-glass process without any increasing of fabrication complexity. The fabricated gyroscope was vacuum-packaged to ~100Pa and then mounted on an analog PCB for close-loop drive and pickoff read-out. The measured sensitivity was 9.1 mV/(°/s) while the non-linearity is 0.913% with the full scale of 1000°/s. The tested noise floor is 0.02°/s /Hz^1/2.