集成隐藏式3维梳齿电极驱动器的低吸合电压CMOS-MEMS微镜阵列  

Low Pull-in Voltage CMOS-MEMS Micro-Mirror Arrays with Integrated Hidden Vertical Three-Dimension Comb Driver

作　　者：程正喜[1] 刘亦 徐鹤靓 康晓旭[2] CHENG Zhengxi;LIU Yi;XU Heliang;KANG Xiaoxu(Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China;Process Technology Department, Shanghai IC R&D Center, Shanghai 201210, China)

机构地区：[1]中国科学院上海技术物理研究所,上海200083 [2]上海集成电路研发中心,上海201210

出　　处：《复旦学报（自然科学版）》2022年第1期61-68,共8页Journal of Fudan University：Natural Science

基　　金：国家自然科学基金(61874127);上海浦江人才计划(18PJ1410700)。

摘　　要：微镜阵列芯片是大尺寸画面投影显示系统的主流光学图形产生器。针对德州仪器公司的数字微镜芯片中微镜吸合电压较高的问题,本文采用CMOS后端金属互连层制备隐藏垂直梳齿电极驱动的低吸合电压微镜,在CMOS后端工艺中基本完成MEMS微镜阵列的结构制备,然后在CMOS工艺后附加少量的Post-CMOS工艺。我们采用0.35-μm 2-Poly-4-Metal(2P4M)CMOS工艺设计和制造了2种1×8规模集成了隐藏式梳齿驱动器的静电驱动双稳态微镜阵列,并且片上集成了CMOS驱动电路。微镜尺寸为18μm×18μm,像素间距为20μm,占空比为81.0%。采用有限元仿真软件计算了微镜结构的电力耦合特性。在大气环境下,仿真结果表明:具有TiN/Al/TiN扭臂的微镜A的静态吸合电压为19.25 V,具有TiN/Al/TiN扭臂的微镜B的静态吸合电压为3 V。测试结果表明:微镜A典型的吸合电压为21 V,与仿真结果接近。微镜A和B吸合电压正在逐步实现与CMOS电路工作电压兼容,可以将驱动电路与微镜阵列单片集成,从而为实现工艺和工作电压与CMOS工艺全面兼容的数字微镜阵列奠定了基础。Micro-mirror array chip is the most vital image generator in the large size format picture image projection display systems.To reduce high operation voltage of the Texas instruments micro-mirror arrays,we developed a micro-mirror array with hidden vertical comb-drive by the CMOS back-end-of-line metal layers through a CMOS process with limited additional process steps.We present two 1×8 scale multi-layer electrostatic bi-stable micro-mirror arrays with hidden vertical comb drive designed by using the standard 0.35-μm 2-Poly-4-Metal(2P4M)CMOS process.The micro-mirror arrays are monolithcally integrated with shift-register linear arrays as the driver.The mirror is 18μm×18μm.The pitch of the pixel is 20μm,resulting the fill factor of 81.0%.The electro-mechanical properties of the mirror are simulated by using finite-element method(FEM)software.The simulated pull-in voltage of the micro-mirror A with TiN/Al/TiN hinges is close to 19.25 V,and the pull-in voltage of the micro-mirror B with TiN/Air/TiN hinges is about 3 V at atmospheric pressure.The tested pull-in voltage of the micro-mirror A with TiN/Al/TiN hinges are 21 V typically.The pull-in voltages of the micro-mirror A and B are approaching to be compatible with CMOS technology operation voltage.The fabricated monolithcally integrated chips verify the feasibility of a micro-mirror array with full compatibility both with process and operation voltage of CMOS technology.

关 键 词：微镜 吸合电压 垂直3维梳齿电极驱动器 

分 类 号：TN27[电子电信—物理电子学]