Abstract:

A novel micro-scale silicon film bending fatigue testing device based on the electrostatic force by comb driver was designed,which can be fabricated by means of the typical surface micromachining technology.The capacitance and the electrostatic force were analyzed theoretically for the designed arc-shaped comb driver. Based on the results of theoretical deduction,the device was analyzed by the modal and harmonic modules of the finite element analysis software ANSYS.The simulation results show that when the applied AC voltage frequency corresponds to the first frequency of the device,the specimen can obtain the maximum stress at the root of the notch. The maximum stress is proportional to the product of the applied DC bias voltage and AC voltage, which is used to evaluate the range of the test voltage.The analysis and observation of the fabrication results indicate that the designed device can satisfy the test requirements perfectly.

Key words: micro-electro-mechanical system design;fatigue;thin film;comb driver;FEA

摘要：

根据梳状驱动器原理设计了一种静电力驱动的硅微薄膜弯曲疲劳试验装置，所设计的装置可以由微机电系统表面牺牲层标准工艺制作加工。对所设计疲劳试验装置的圆弧梳状驱动器电容及静电驱动力进行了理论分析，并在此基础上采用有限元分析软件ANSYS对装置进行了模态分析与简谐分析。分析结果表明：当所施加的交流电压频率与结构的一阶固有频率相等时，试样在其缺口根部取得最大应力值，该应力值与所加交直流电压乘积的大小成线性关系，利用该关系式可对试验所需电压值进行预测。有限元分析和制造结果观测表明，所设计的装置符合微机械疲劳试验要求。

关键词: 微机电系统设计；疲劳；薄膜；梳状驱动器；有限元分析