微机械谐振器可变锚点结构能量耗散特性分析

摘要

微机械谐振器在振动过程中总会产生能量耗散，并且具有诸如空气阻尼耗散、热弹性阻尼耗散、锚点结构耗散、表面耗散等诸多耗散机制，其中锚点结构耗散是一种主要的能量耗散机制。应用完美匹配层方法，将无限大区域入射波的吸收问题转化到有限区域内进行。针对中心支撑圆盘体模态谐振器，设计两种不同的锚点支撑结构，并分别讨论其几何结构的变化对谐振器固有频率和锚点损耗品质因子的影响。结果证明通过调整锚点结构，可以大幅度提高谐振器的锚点耗散品质因子，提高能量的利用效率。%Energy dissipation of micromechanical resonators is always inevitable in vibration process. There are several energy dissipation mechanisms, such as air damping dissipation, thermo-elastic damping dissipation, anchor loss, surface dissipation and so on. Of them, anchor loss is the main energy dissipation mechanism. In this paper, the perfectly matched layers method was adopted to transform the incident wave absorption problem in infinite domain into that in finite domain. Two different anchor structures of centrally-supported bulk-mode disk resonator were designed. And the influence of the geometrical changes of the structure on the inherent frequencies and anchor loss quality factor of the bulk mode disk resonator was discussed. The results show that the anchor loss quality factor can be greatly improved and the energy utilization efficiency can be raised by changing the anchor structure of the resonator.