A micromachined vibrating gyroscope

Abstract

Abstract A vibrating microgyroscope with a thin polysilicon resonator fabricated by silicon surface micromachining is described. The 400 μm × 800 μm resonator is driven in a lateral direction by electrostatic force, and the angular rate is detected as the capacitance change between the resonator and its substrate. Mechanical Q -factors for the driving mode and the detecting mode of the polysilicon resonator are 2800 and 16 000, respectively, at pressures below 0.1 Pa. Methods are presented for modifying the difference between the resonance frequencies of the driving and detecting modes. The test device shows a noise-equivalent rate of 2° s −1 .