PVDF压电薄膜传感器的制作研究

传感器的制作是利用的28μm厚的4层结构的PVDF压电薄膜,传感器表面电极形状的制作采用了剪切加丙酮腐蚀的方法,保证了传感器有一定的非金属化的边缘.对于电极的引出,我们的设计是将传感器上、下电极面引脚错开,引出电极是我们比较容易做到的穿透式,我们用了压接端子压接和空心小铆钉铆接的两种方法.     

基于PVDF的高压电性薄膜制备工艺研究

针对国内的聚偏二氟乙烯(PVDF)压电传感器仅限于实验室阶段,仍需要大量进口的现状,通过对PVDF压电特性分析,结合传感器产品的结构,进行PVDF压电传感器的制备工艺的研究。对工艺过程中的初始薄膜制备、单轴拉伸、高压极化和磁控溅射等主要工艺进行制备工艺参数的探索,获得了PVDF压电敏感薄膜,并采用聚酰亚胺材料进行封装,得到PVDF压电传感器。对该传感器进行关键参数静态压电系数d_(33)的测试,结果为13.1PC/N,获得了满足实际工程使用的PVDF压电传感器产品。     

PVDF压电传感器在爆炸冲击波测量中的应用

本文介绍了PVDF压电传感器的测压原理,并通过实验数据说明了PVDF压力传感器具有响应快、灵敏高、测压范围宽等特点,是一种理想的爆炸冲击波测压传感器;同时也说明了UHMWPE复合材料具有轻质,吸收冲击波效率高等特性,在爆炸冲击波防护领域有很好的应用前景.     

PVDF压电薄膜制作传感器的理论研究

用PVDF压电薄膜设计传感器是近年来在传感器领域研究的一个新热点,通过对PVDF压电薄膜的压电性能的分析,根据弹性力学的薄板理论和压电效应的物态方程,导出PVDF压电薄膜的传感方程,并对偏转角口的情况进行了讨论;为用PVDF压电薄膜制作传感器提供理论基础。     

肘部压力对PVDF传感器压电信号响应

设计了一种可嵌入服装的柔性压电传感器,对人体肘部运动进行弯曲力压电性能检测.以聚偏二氟乙烯(PVDF)静电纺纤维膜为基础,封装传感器芯片,为了优化传感器的测试性能,采用多层传感芯片结构以提高薄膜传感器信号响应,并记录手臂在不同弯曲状态下的压电响应信号,实际测试结果表明:双层电纺传感芯片结构具有明显的压电信号响应优势,弯曲力比正压力下的压电信号响应更为明显.     

PVDF压电加速度传感器电荷灵敏度影响因素分析

建立PVDF压电模型,依据压电方程和加速度计基本原理,推导和分析了PVDF压电薄膜加速度传感器电荷灵敏度的影响因素,并设计实验进行了验证.公式推导和实验证明,PVDF压电加速度传感器电荷灵敏度随压电薄膜的面积增大而增大,随厚度增大而减小.,随预紧弹簧的刚度增大而减小.     

光刻技术在PVDF压电薄膜电极制作中的应用

为了在聚偏二氟乙烯(PVDF)压电薄膜上得到特定形状和尺寸的金电极,利用光刻技术的基本原理,分别实施了2种制备方案,即正性胶保护法和负性胶保护法。实验结果表明:负性胶保护法不能用于PVDF压电薄膜金电极的制作,而正性胶保护法能够成功地完成PVDF压电薄膜上金电极的制作,并已经成功地应用于高频超声换能器研制中。     

压电传感器与前置放大器的配接

从提高传感器和测量电路的灵敏度出发,根据压电传感器压电元件串联和并联2种连接方式,电压放大器和电荷放大器2种前置电路的特点,对压电传感器与前置电路如何配接进行研究。提出了压电元件串联应配接电压放大器,压电元件并联应配接电荷放大器。当压电传感器与测量电路之间的距离较远时,宜采用后一种方式。此方法具有实际的指导意义。     

PVDF传感器在水中爆炸弱压力信号测量中的应用

为了研究水中爆炸微弱压力信号的测试方法,采用聚偏氟乙烯（ PVDF）压电薄膜作为敏感元件制成带内装放大电路的传感器,在试验水池中进行小药量的爆炸试验,验证利用PVDF传感器进行水中爆炸微弱压力信号测量的可行性。试验结果表明：PVDF压电薄膜传感器在5g TNT炸药水池爆炸压力测量中,得到了冲击波和气泡脉动压力曲线,波形一致性较好。PVDF传感器具有频响高、灵敏度高、制作简单、成本低的优点,可以用于水中爆炸微弱压力信号的测量。     

高压静电纺丝工艺制备PVDF-ZnO/GR共聚物膜的压电性能研究

提出了一种利用高压静电纺丝工艺制备PVDF/ZnO及PVDF/Graphene(以下简称GR)共聚物膜的方法并对其压电性能进行了研究。通过在传统的PVDF溶液中混入氧化锌和石墨烯,制备得到PVDF共聚物膜,对PVDF,PVDF/ZnO,PVDF/GR三种膜进行电镜扫描以表征其表面结构。对三种压电薄膜进行了压电响应对比实验,PVDF,PVDF/ZnO,PVDF/GR三种薄膜的压电响应峰值分别达到16.8 V,29.6 V,21.7 V。PVDF/ZnO压电薄膜对比PVDF压电薄膜的电压峰值提高12.8 V。PVDF/GR压电薄膜对比PVDF压电薄膜的电压峰峰值提高了4.9 V。对三种压电薄膜进行了能量收集实验,PVDF,PVDF/ZnO,PVDF/GR三种薄膜分别令LED灯点亮11.3 s,17 s,14.6 s,输出功率密度为6.79μW/cm^2,19.28μW/cm^2,15.11μW/cm^2。PVDF共聚物膜对比PVDF膜在压电性上有显著提高,可应用于压电能量收集或可穿戴传感器等应用领域。     

微型硅基弯曲板波器件

介绍了基于ZnO压电薄膜的微型弯曲板波(FPW)器件的设计与制作。为减小薄膜的应力,器件采用LTO/ZnO/LTO/Si3N4多层复合板结构,并采用直流磁控溅射工艺制备ZnO压电薄膜,在压电复合板结构上沉积两对叉指电极,分别用于Lamb波的激发和接收。X射线衍射分析表明,沉积的ZnO薄膜C轴高度择优;扫描电子显微镜分析表明,制备的ZnO薄膜平整、致密,晶粒生长呈现明显的柱状结构;通过分析制备的高次谐波体声波谐振器(HBAR)器件性能来间接检验ZnO压电薄膜的电学性能,HBAR器件的品质因子较高,表明薄膜有较好的压电性能。利用安捷伦E5071C网络分析仪检测FPW器件的频率响应,结果表明反对称A0模式Lamb波的实测中心频率与理论计算的频率结果基本一致。     

PVDF压电薄膜在结构监测中的应用初探

本研究对采秀ＰＶＤＦ压电薄膜监测结构的基本特性进行了较为系统的研究，分别做了ＰＶＤＦ压电薄膜监测结构的静态和动态响应实验，实验结果表明，ＰＶＤＦ压电薄膜监测结构应变的灵敏度提高，其静态响应的线性度好很好，而其动态响应同则有非线性和迟滞现象，对于用ＰＶＤＦ压电薄膜监测结构的冲击载荷也进行了初步的研究，实验结果表明采用ＰＶＤＦ压电薄膜可以实时监测结构所受的冲击载荷，并能及时反应出结构所受到的冲击损伤。     

Self-alignment observation and conductivity evaluation in micro chips integration with square binding pattern

A “square” binding alignment pattern, with relatively higher energy barrier but four fully aligned orientations at four off-set angles of 0°, 90°, 180°, and 270°, has been analyzed by introducing a concept of the overlap ratio, compared to a “rectangular” one. Both the “square-pattern” micro-chips and the substrate with the “square-pattern” binding sites were fabricated using one-mask micromachining process, and the self-alignment in situ observation under three different off-set orientation angles of 35°, 46°, and 90° was demonstrated using a high-speed video camera. Sequential images reveal a slow translational motion in the early stage followed by a faster rotational alignment. A novel technique has been further proposed for the conductivity evaluation by using three kinds of SAM films, i.e., C12, C18, and Terphenyl. The preliminary measurements indicate that, using the proposed novel structure, the Terphenyl film is believed to be desirable as a conductive SAM film for self-alignment of micro-chips.     

ZnO压电薄膜声传感器的有限元分析

阐述了ZnO压电薄膜声传感器的结构和工作原理,并用ANSYS 9.0对压电薄膜声传感器进行了静态分析、模态分析和谐响应分析。通过静态分析,得到压电薄膜声传感器的灵敏度为16.4 mV/Pa;模态分析得出了传感器的第一阶固有频率为12.379 kHz;谐响应分析则获得感应电压与动态外力频率之间的关系。这些分析为此类声传感器的设计提供了理论依据。     

双压电结构乐甫波激发效率和液体传感的仿真

乐甫波器件适于液体检测,但在工程上经常因为激发效率较低而影响应用。与“压电基底-非压电薄膜”的单压电结构乐甫波器件相比,双压电结构的特点是薄膜也选用压电材料,以期增大器件整体的压电效应。在建立理论模型的基础上,通过空气中和液体检测时双压电结构乐甫波与声表面波、单压电结构乐甫波的机电耦合系数仿真并对比,表明对于某些压电基底和薄膜,双压电结构具有更高的乐甫波激发效率。并且,以液体介电常数检测为例,仿真结果还表明了双压电结构乐甫波比单压电结构具有更高的灵敏度。     

Integration of displacement sensor into bulk PZT thick film actuator for MEMS deformable mirror

Bulk PZT thick film actuator integrated with displacement sensor, the so-called self-sensing actuator, is presented in this paper. The PZT film is used as not only an actuating layer but also a displacement sensor, which is achieved by dividing the electrode on the top surface of the PZT film into two parts: central top electrode for actuating and outer annular sensor electrode for piezoelectric displacement detection. When the actuator moves, the piezoelectric charge is induced in the outer annular PZT due to the piezoelectric effect. The total amount of accumulated charge is proportional to the stress acting on the PZT, which is in turn proportional to the actuator displacement. By collecting the piezoelectric charge, the actuator displacement can be detected. A theoretical model is proposed to determine the structure parameters of the sensor and predict the sensor sensitivity. Experiments were performed on the micro-fabricated sensor integrated PZT thick film actuator, and the measured piezoelectric charge is close to the theoretical predictions. The integrated piezoelectric sensor has a displacement sensitivity of approximately 4 pC/nm. In addition, the integration of displacement sensor into the actuator needs no additional fabrication process and has no influence on the actuator performances.     

On stress singularity at the interface edge between piezoelectric thin film and elastic substrate

This paper deals with the modeling aspects of the stress singularity at the interface edges between piezoelectric thin film and elastic substrate. The electro-elastic problem of a transversely isotropic piezoelectric thin film attached to an elastic substrate is treated theoretically. Emphasis is placed on the investigation of the singularity in the stress field at the free edge of interface. The eigen-equation determining the order of the singularity is derived. Numerical results for two edge geometries are presented for PZT film/silicon substrate combinations. It is shown that the orders of the stress singularities range from 0.1 to 0.3 for the considered cases. Moreover, piezoelectric effects may alter the singularity order to some extent, but not significantly.     

双通道压电式密度传感器的研究

在同一压电石英晶片上制备两个石英晶体谐振器 ,实验结果表明双通道之间的相互干扰可以忽略。在石英晶体表面修饰多孔TiO2 膜层 ,可大大提高传感器对液体密度的灵敏度。采用两个修饰不同厚度TiO2 膜层的双通道压电传感器的频率差作为测量信号 ,可以消除液体粘度的影响 ,并获得与液体密度有良好线性关系的工作曲线 ,实现液体密度的测定