具有多孔双微结构层的柔性电容式压力传感器  

Flexible Capacitive Pressure Sensors with Porous Double-Microstructure Layers

作　　者：孙翰轩 陈盛华[1] 徐策 王志华[1] Sun Hanxuan;Chen Shenghua;Xu Ce;Wang Zhihua(State Key Laboratory of Reliability and Intelligence of Electrical Equipment,School of Electrical Engineering,Hebei University of Technology,Tianjin 300130,China;China Petroleum Liaohe Equipment Company,PanJin 124000,China)

机构地区：[1]河北工业大学电气工程学院省部共建电工装备可靠性与智能化国家重点实验室,天津300130 [2]中国石油渤海装备辽河钻采装备分公司,辽宁盘锦124000

出　　处：《微纳电子技术》2024年第4期105-113,共9页Micronanoelectronic Technology

基　　金：河北省第三批青年拔尖人才支持计划;天津市自然科学基金(8JCYBJC87100);天津市科学技术普及项目(22KPXMRC00020)。

摘　　要：电极和介电层的材料性能和表面结构是决定柔性电容式压力传感器性能的关键因素。将碳纳米管(CNT)与硅橡胶结合制备出拉伸性能优良的斜线型微结构电极层。以聚二甲基硅氧烷(PDMS)/BaTiO_(3)/SrTiO_(3)复合材料制备多孔砂纸微结构介电层。电极与介电层交界面构成双重微结构以提升电荷携带能力。场发射扫描电子显微镜与光学显微镜观测结果验证了上述微结构的存在。基于电容模型的分析表明,传感器灵敏度主要取决于多孔介电层的形变量。所制备的多孔双微结构层柔性电容式压力传感器最高灵敏度为2.681 kPa^(-1),在3~5 kPa的压力区间仍具有0.412 kPa^(-1)的灵敏度,响应时间和释放时间分别约为39和61 ms。该传感器能够检测出吞咽时咽部运动的微小压力,实验中测得的最小电容变化率为0.13%,能够识别0.53 Pa的微小压力,具有较低的检测限。进行6000次以上的压缩循环测试后,传感器加载-卸载曲线重合性好,同时对不同频率压力的响应良好,验证了传感器良好的可重复性。总之,所提出的传感器具有良好的压力感知性能,在生理信号监测、人机交互等领域具有广阔的应用前景。The material properties and surface structures of electrodes and dielectric layers are key factors that determine the performance of flexible capacitive pressure sensors.Carbon nanotubes(CNTs)were combined with silicone rubber to prepare a diagonal microstructure electrode layer with excellent tensile properties.The porous sandpaper microstructure dielectric layer was prepared by polydimethylsilane(PDMS)/BaTiO_(3)/SrTiO_(3)composite material.The interface between the electrode and dielectric layer forms a double-microstructure to improve the charge carrying capacity.The observation results of field emission scanning electron microscopy and optical microscopy confirm the existence of the above-mentioned microstructure.The analysis based on the capacitance model shows that the sensitivity of the sensor mainly depends on the shape variable of the porous dielectric layer.The maximum sensitivity of the prepared flexible capacitive pressure sensor with the porous double-microstructure layers is 2.681 kPa-1,the sensitivity is 0.412 kPa^(-1)at the pressure range of 3-5 kPa,and the response time and release time are about 39 ms and 61 ms,respectively.The sensor can detect the small pressure of the pharyngeal movement during swallowing,and the minimum capacitance change rate measured in the experiment is 0.13%.It can recognize the small pressure of 0.53 Pa and has a lower detection limit.After conducting more than 6000 times compression cycle tests,the coincidence of loading-unloading curves for the sensor is good,and the response to pressures at different frequencies is good,verifying the good repeatability of the sensor.In summary,the proposed sensor has good pressure sensing performance and broad application prospects in fields of physiological signal monitoring and human-computer interaction.

关 键 词：柔性电容式传感器 多壁碳纳米管 压力传感器 双微结构层 纳米钛酸钡 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]