The Design And Research Of Balancing-force MEMS Gyroscope Based On Tunneling Effect

Through fully studying an analyzing the development of the vibrating micromechanical gyroscope at home and abroad, most silicon micromechanical gyroscopes make use of capacitive detection of the output signals. As the dimension of the gyroscopes decrease, the resolution of traditional capacitive detection technique also decreases, resulting in a low SNR of the output signals. So a new detection method will be designed to measure minimal changes in the position of a tunnel-effect gyroscope in this paper, the tunnel-effect gyroscope adopts the orthogonal-beam structure to weaken the coupling error. The accurate matching of the natural frequencies in drive mode and sense mode ensures the high sensitivity of the gyroscope.The design theoretical foundation of tunnel-effect micromechanical gyroscope is introduced in this paper at first. By means of analyzing the fundamentals and dynamic equation of micromechanical vibrating gyroscope, the influence of operating frequencies on the detection sensitivity and bandwidth of the device has been discussed, and the electrostatic drive and tunneling current detection involved in gyroscope design is introduced simply. The air damping, parasite Coriolis force and interference from axial accelerations are also discussed.This paper describes the design of a novel orthogonal-beam gyroscope based on the principle of tunnel effect. By means of analyzing the operating principle and structure of gyroscope, the mechanical performance, structure damping, electrostatic driving force and mechanical coupling error are analyzed systematically. Finally the structure of tunnel-effect micromechanical silicon gyroscope is get with higher sensitivity.According to the fabrication technology, an entire series of independent processes for micromechanical tunnel-effect gyroscope fabrication and the layout is designed. And the gyroscope structure is processing. Finally, we have also studied feedback control methods of tunnel-effect gyroscope, analyzed kinds of common tunneling current detection circuit at home and abroad. Based these, the preliminary research for tunneling current detection circuit method is made.