A bionic approach for the mechanical and electrical decoupling of an MEMS capacitive sensor in ultralow force measurement  

作　　者：Wendi GAO Bian TIAN Cunlang LIU Yingbiao MI Chen JIA Libo ZHAO Tao LIU Nan ZHU Ping YANG Qijing LIN Zhuangde JIANG Dong SUN 

机构地区：[1]State Key Laboratory for Manufacturing Systems Engineering,International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technologies,Overseas Expertise Introduction Center for Micro/Nano Manufacturing and Nano Measurement Technologies Discipline Innovation,Xi’an Jiaotong University(Yantai)Research Institute for Intelligent Sensing Technology and System,School of Mechanical Engineering,Xi’an Jiaotong University,Xi’an 710049,China [2]Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing,Yantai 265599,China [3]State Key Laboratory of Robotics and Systems(HIT),Harbin 150006,China [4]Beijing Advanced Innovation Center for Intelligent Robots and Systems,Beijing Institute of Technology,Beijing 100081,China [5]Department of Biomedical Engineering,City University of Hong Kong,Hong Kong,China

出　　处：《Frontiers of Mechanical Engineering》2023年第2期297-317,共21页机械工程前沿（英文版）

基　　金：supported in part by the National Natural Science Foundation of China(Grant Nos.52105589 and U1909221);in part by the China Postdoctoral Science Foundation(Grant No.2021M692590);in part by the Fundamental Research Funds for the Central Universities,China(Grant No.xzy012021009);in part by the State Key Laboratory of Robotics and Systems(HIT),China(Grant No.SKLRS2021KF17);in part by the Beijing Advanced Innovation Center for Intelligent Robots and Systems,China(Grant No.2019IRS08).

摘　　要：Capacitive sensors are efficient tools for biophysical force measurement,which is essential for the exploration of cellular behavior.However,attention has been rarely given on the influences of external mechanical and internal electrical interferences on capacitive sensors.In this work,a bionic swallow structure design norm was developed for mechanical decoupling,and the influences of structural parameters on mechanical behavior were fully analyzed and optimized.A bionic feather comb distribution strategy and a portable readout circuit were proposed for eliminating electrostatic interferences.Electrostatic instability was evaluated,and electrostatic decoupling performance was verified on the basis of a novel measurement method utilizing four complementary comb arrays and applicationspecific integrated circuit readouts.An electrostatic pulling experiment showed that the bionic swallow structure hardly moved by 0.770 nm,and the measurement error was less than 0.009% for the area-variant sensor and 1.118% for the gap-variant sensor,which can be easily compensated in readouts.The proposed sensor also exhibited high resistance against electrostatic rotation,and the resulting measurement error dropped below 0.751%.The rotation interferences were less than 0.330 nm and(1.829×10^(-7))°,which were 35 times smaller than those of the traditional differential one.Based on the proposed bionic decoupling method,the fabricated sensor exhibited overwhelming capacitive sensitivity values of 7.078 and 1.473 pF/μm for gap-variant and area-variant devices,respectively,which were the highest among the current devices.High immunity to mechanical disturbances was maintained simultaneously,i.e.,less than 0.369% and 0.058% of the sensor outputs for the gap-variant and area-variant devices,respectively,indicating its great performance improvements over existing devices and feasibility in ultralow biomedical force measurement.

关 键 词：micro-electro-mechanical system capacitive sensor BIONICS operation instability mechanical and electrical decoupling biomedical force measurement 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]