静电驱动连续面形微机电系统变形镜的制作

Fabrication of Electrostatically Actuated MEMS Deformable Mirror with Continuous Surface

基于三层多晶硅表面加工工艺和自适应光学经验公式,设计并制作了一种静电驱动的16单元连续面形微机电系统(MEMS)变形镜(DM),并用ZygoNewView7300白光干涉仪对样片的静态特性和动态响应特性进行了测试。静态测试结果表明,器件在150 V电压下的最大形变量为0.667μm,相邻单元之间的交联值为9%,镜面位置重复性为10%。动态测试结果表明,器件对正弦驱动信号的响应时间小于30μs,响应曲线近似为一条余弦曲线,谐振频率为36 kHz。该变形镜可用于自由空间光通信、激光光束整形、波前畸变校正、投影显示、生物医学成像和人眼视差校正等重要领域。

Based on a three-layer polysilicon surface micromachining process and some experience formulas of adaptive optics,an electrostatically actuated microelectromechanical systems（MEMS） deformable mirror（DM） with 16 actuators and continuous surface is designed and fabricated.Both static and dynamic characteristics of the prototype are tested using a scanning white light interferometer ZygoNewView7300.The result from the static test shows that the displacement of the actuator is 0.667 μm at 150 V,the interaction between the neighboring actuator is 9%,and the position repeatability of the surface of DM is 10%.At the same time,the result from the dynamic test shows that the response time of the prototype is less than 30 μs and a cosine curve is observed under a sine driving signal.The resonance frequency of the actuator is about 36 kHz.This type of DM can be used for free space optical communication,laser beam shaping,wavefront correction,projection,biomedical imaging and human eye aberration correction.