System-Level Results of a High Sensitivity Vibrating MEMS Gyroscope Fabricated with The BDRIE-HS* Technology

In this paper we report on the system setup and initial system characterization of our vibrating mass, tuning fork gyroscopes that implement the BDRIE‑HS* (bonding and deep reactive ion etching for high sensitivity) technology. Enabled by this technology, the capacitive sensitivity of the sense electrodes of the two-mass tuning fork gyroscope are improved by a factor of 2.8 and the sense Q factors are increased by a factor of approx. two as well. We fabricated functional MEMS gyroscopes with varying gap and also varying area sense electrodes. The MEMS elements were assembled with our ASIC stacked on top of the MEMS element into a CLCC44 ceramic package. The measurements of those systems show very promising results (ARW down to 0.01 °/√h and BI down to 0.02 °/h). The ASIC allows to adjust several system parameters such as the drive amplitude, frequency spacing, the CSA gain and thereby the scale factors, in order to find the optimum configurations for the new sense electrode designs. We discuss the results of these investigations in comparison to our reference systems.