提出了一种用于双稳态MEMS继电器的面外运动金属基聚合物电热微驱动器,下层结构使用了环氧树脂型SU-8胶作为驱动层,中间层为蛇形镍电阻丝发热层,上层结构为金属偏置层,构成的多层膜结构在常温下保持悬空部分平直,通电时产生的焦耳热使微驱动器件发生面外运动。先对设计的微驱动器进行了概念分析,再利用ANSYSTM有限元分析软件的多物理场(电-热-机械耦合)对热驱动器的性能进行了仿真与优化。当SU-8驱动层厚度、热电阻丝厚度、偏置层厚度比分别为12:4:4μm时,所设计器件的驱动性能最佳,即在0.4V驱动电压下,响应时间10ms时微驱动器产生驱动位移28μm,输出力为1mN,功耗为10mW。
A new polymeric out-of-plane electrothermal microactuator embedded with metal was proposed.The microactuator consists of a passive Nickel layer and a functional expanding SU-8 layer,packaging with a winding S-shaped Ni heater.When exciting with a pulse current,the multilayer actuator is able to maintain a suspended structure to produce an out-of-plane movement vertical to the substrate.The proposed device is conceptually advanced.By means of finite element(FE) simulation with ANSYSTM multi-physical coupling module(electro-thermal-structure),the geometric structure is optimized and electrothemal capabilities are determined theoretically.When the high ratio of actuating SU-8 layer,heating layer and passive Ni layer is 12:4:4 μm,the actuation capabilities will obtain to the maximum.That is,under 0.4V driving voltage the displacement of the prepared actuator is 28μm in the 10ms response time,output force 1mN,and power consumption 10mW,respectively.