微加工静电排斥驱动器特性分析

摘要

基于非均匀电场可产生静电排斥力的原理,设计制造了单元尺寸为300 μm的MEMS静电排斥型离面驱动器.此驱动器不受静电吸合效应的限制,行程较传统静电吸引型驱动器有显著提高.利用表面硅工艺完成了该驱动器的加工.为研究静电排斥型驱动器的动态响应特性,建立了该驱动器的等效模型并利用数值计算方法分析了驱动器的压膜阻尼特性和幅频特性.采用白光干涉仪对微驱动器进行了静态和动态测试,测试结果表明,所设计的MEMS静电排斥驱动器在100V的电压下实现了2.1μm的驱动位移,工作带宽为2kHz,具有较快的响应速度.%Based upon the principle that an asymmetric electric field can generate a repulsive force, a micro out-of-plane electrostatic repulsive actuator with a unit dimension of 300 urn is designed and fabricated. The stroke of this kind of actuator is far larger than the traditional attractive actuators for it is not limited by the "Pull-in" phenomenon. The actuator is prepared using a surface micromachining polysilicon processes. To study the dynamic performance of the actuator, an equivalent model of the electrostatic repulsive micro driver is proposed. The squeeze air film damping -effect and frequency response of the micro driver are analyzed based upon the numerical method. The static and dynamic characteristics of the actuator are tested using a white light interferometer. The results show that the static displacement of this kind of actuator reaches 2.1 μm at 100 V, and the actuator has a wide working bandwidth of 2 kHz and a fast response μ