A Novel Sixteen-Sided Cobweb-Like Disk Resonator Gyroscope with Low As-Fabricated Frequency Split between Drive and Sense Modes

A novel sixteen-sided cobweb-like disk resonator gyroscope has been proposed and studied in this work. The resonator has a hexadecagon shape disk which consists of 10 concentric sixteen sided cobweb rings connected through 8 alternating spokes to a single central anchor. The devices have been fabricated using a SOI silicon to silicon fusion bonded process and have been hermetically vacuum sealed using a wafer-level packaging (WLP) process. A frequency split of 0.56 Hz between drive and sense modes has been obtained for an as-fabricated resonator at resonant frequency 18.719 kHz (Δf/f~29.9 ppm). It means that operational mode symmetry of this new type of gyroscope is insensitive to fabrication tolerance. The frequency split can be further reduced to 0.01 Hz by applying low electrostatic voltages of 4.2 V and 7.55 V on the electrodes of 45° and 67.5°, which would significantly reduce power supply and simplify detection circuit. Q-factor and decay time constant are measured to be 113k and 1.92s, respectively.