A micromachined vibrating gyroscope

A vibrating micro-gyroscope with a thin polysilicon resonator of 400 x 800 pmz was fabricated by silicon surface micromachining. The gyroscope is driven in a lateral direction by electrostatic force, and detects output signals from a capacitance change between the resonator and the substrate. Mechanical Q factors of 2,800 and 16,000 were obtained for the driving mode and the detecting mode of the polysilicon resonator, respectively, at pressures below 0.1 Pa. Methods were presented for modifying the difference between the resonant frequencies of the driving and the detecting modes. The noise equivalent rate of the test device is 7 de&.