梳齿结构与振动梁复合的硅微谐振器的非线性分析

The output signal of the resonant MEMS sensor is a frequency signal, which has the advantages of high precision and strong anti-interference ability. It is one of the important development directions of micro sensors. However, the non-linearity of the vibration of this type of sensor will cause vibration amplitude noise to be coupled to the frequency output and adversely affect the noise performance of the device. Therefore, it is very important to analyze the nonlinear vibration characteristics of the resonant accelerometer. Taking the resonator with vibrating beam integrated with comb fingers structure as research object, the force-displacement equation and the vibration differential equation of the resonant beam were derived. Compared with the experimental results, the curves are in good agreement, which proves the correctness of the theory. At the same time, the results show that the mechanical nonlinearity of the structure is mainly affected by the thickness of the resonance beam; the critical state of nonlinear instability will cause the structure to jump in frequency. Increasing structural damping can effectively increase the displacement of the stable response of the system and the output voltage signal. In addition, devices designed under the jump-up frequency after structural nonlinear instability have good stability.