An Improved Fabrication Process for Micro Hemispherical Resonator Gyroscope

Abstract

This paper reports an improved fabrication process for micro hemispherical resonator gyroscope $(\mu \mathbf{HRG})$, which enhance consistency of quality factor, frequency and capacitance gaps. Micro hemispherical resonator is formed from fused silica substrate through thermal deformation on fast whirling platform individually. Following procedures including laser ablation, metallization and integrating to electrodes are accomplished on wafer-level and optimized through experimental data. The resonators are electrically characterized in vacuum chamber. Frequency for $\mathrm{n}=2$ wineglass mode ranges from 7kHz to 8kHz and quality factors range from 100,000 to 160,000, which are significant to stabilize and enhance gyro's performance. The accomplished device operates in force-rebalance mode in vacuum packaging, realizing a full-scale range above $\pm 200\deg/\sec$ and bias instability of 0.63 deg/hr.