MEMS微梁静电致动器的力学特性研究

采用降阶建模法对多晶硅／氮化硅复合悬臂粱静电致动器的多物理场耦合问题进行了仿真计算。悬臂粱在氮化硅残余应力的作用下弯曲翘起。在微粱和基底间施加电压后，微粱受到向下电场力的作用，当电压超过阈值后微粱就会被吸到基底上。通过提取系统的各阶模态及其对系统的贡献，对各阶模态进行组合来取代该结构的耦合域，从而达到对耦合问题降阶的目的。采用该方法算得微粱的翘起高度、1阶固有频率和吸下的阚值电压与实验测得的结果吻合较好。

Research on Mechanical Properties of MEMS Cantilever Actuator Based on the Reduced Order Modeling

This paper presented a novel method for generating reduced-order model(ROM) for the polysilicon-silicon nitride cantilever.The cantilever was curved under the residual stress of Silicon Nitride,and the cantilever was pulled after the execution of a potential between it and the substrate.When the potential exceeded the pull-in voltage,the cantilever was pulled down to the substrate.ROM extracted the eigenmodes and their contribution factors.The coupled-physics domain was represented by a factored sum of mode shapes.So the problem was simplified and the operation quantity was greatly reduced.The calculated results for the height of the cantilever tip,first mode frequency and pull-in voltage are in good agreement with experimental results.