基于FBG温度解耦的光纤法布里-珀罗 高温压力传感器

本文提出了一种基于光纤布拉格光栅(FBG)温度解耦方法的光纤法珀(FP)压力传感器,该传感器采用低温共烧陶瓷(LTCC)技术实现批量化制作.通过在膜片式压力传感器的基础上集成光纤布拉格光栅(FBG),实现温度、压力双参数测量;提出温度解耦方法,对传感器进行温度补偿及压力测量结果的修正.实验结果表明,在20～300℃的温度范围内, FBG温度传感器的灵敏度为0.012 nm/℃,在160 kPa的压力范围内,压力测量灵敏度约为0.1μm/kPa, 3次重复实验的重复性误差和非线性误差分别约为5.6%和1.3%,温度系数为0.018μm/℃,压力灵敏度随温度变化为0.283 nm/(kPa·℃),同时,采用温度解耦方法,得到压力计算值与真实值最大偏差小于2.5 kPa.     

膜片式光纤动态压力传感器的研制

为了更好地满足动态压力的测量需求,研究了一种基于法布里-珀罗（Fabry-Perot,F-P）干涉原理的膜片式光纤动态压力传感器。从理论上分析了多个反射面对F-P腔光谱的影响,提出了得到单一F-P腔的方法。进而采用机械研磨的方式对传感器膜片外表面进行粗化加工,有效解决了由多个反射面带来的光谱复杂问题。对传感器进行静态压力和动态压力标定试验,结果表明：传感器性能良好,在0~200 kPa（表压）范围内的静态压力测量误差小于等于0.5 %FS;在20~2500 Hz范围内,传感器的幅值灵敏度相对误差优于±10%。     

小量程高灵敏度压阻式表压压力传感器的设计北大核心CSCD

针对飞机供氧、液压、环控和燃油等系统故障预测与健康管理(PHM)对小量程压力传感器的重大需求,设计了一种新型梁膜复合结构微电子机械系统(MEMS)压阻式压力传感器,该研究通过小量程、高灵敏度的压力传感器力学机理分析和力学仿真建模,提出一种具有弧形膜和米字梁复合型结构,采用弧形硅杯支撑,通过结构和尺寸的优化设计以及压敏电阻位置的确定,在-2~12 KPa的量程内具有较高的灵敏度和线性度。利用ANSYS软件仿真分析得到设计的压力传感器灵敏度为21.801 mV/KPa,非线性度为0.02%。然后基于MEMS加工工艺设计了SOI表压压力传感器的工艺流程。     

光纤压力传感器制作研究

分析了现有光纤压力传感器的原理与结构,选择非本征型法布里-珀罗腔作为研究目标,建立了测压的数学模型,开展了微机电加工工艺研究,探索了包括研磨、腐蚀、减薄与键合等特殊工艺,批量制作的法布里-珀罗腔具有一致性;建立了一套基于机器视觉的测量与焊接系统,能够在线精确测量与焊接控制,实现光纤与准直管的焊接以及准直管与法布里-珀罗腔的焊接。利用本系统,制作出传感器灵敏度为1.765 nm/kPa,在不采用非线性拟合校正的条件下,膜片挠度-压力的线性度为99%,重复性为1%,迟滞为0.7%,温度敏感系数为0.15 nm/℃,零位长时漂移小于2 nm。     

一种用于复杂环境下的高精度微型谐振式压力传感器北大核心CSCD

微谐振式压力传感器因其体积小、精度高等特点而被广泛研究,本文基于谐振器在不同压力载荷下侧向振动时其等效刚度随轴向应力的改变而变化的原理,设计了一种静电激励/电容检测的谐振式压力传感器。本设计采用的谐振器结构与现有研究不同,通过在谐振梁的两边设计了两根侧梁用于抑制谐振器的Z向位移,提高了传感器的稳定性,并且双面梳齿结构和复合温敏梁可进一步优化传感器检测灵敏度等性能。在ANSYS WORKBENCH仿真平台下对其进行分析与验证,结果表明:侧梁可有效地抑制谐振器的Z向位移,在0~100 MPa范围内谐振器具有良好的正向应力特性;传感器基础谐振频率为29.834 kHz,在0~120 kPa范围内灵敏度可达29.6Hz/kPa,且最大过压1.5×FS时仍具备频率稳定性,这表明该传感器可应用于对灵敏度、抗过压等性能有更高要求的复杂环境中。     

压力测量膜片的形变计算

电容式压力传感器测量膜片的形变，决定了计算压力测量环节中电容值的数学模型．介绍了测量膜片形变方程的建立、推导并对压力测量膜片在不同载荷下的形变特性进行了分析和计算，克服了原有测量膜片形变规律的错误模式。     

一种齐平封装的MEMS高频响压力传感器

设计了一种耐高温、高频响压力传感器芯片,解决了军事爆破工程实际中需要在高温环境中不失真地测量一些变化频率高、压力波形上升快陡的动态压力.基于硅隔离SOI(绝缘体上的硅)技术和MEMS(微型机械电子系统)技术,利用ANSYS对它们进行了量程和固有频率的模拟,并分析计算了加速度灵敏度.对它们进行了齐平结构的封装.避免了管腔效应的影响,得到了一种耐高温、高频响的压力传感器.对其中1 MPa量程的压力传感器进行了动态标定,通过激波管的试验,得到1 MPa压力传感器的响应频率为147 kHz,满足工程实际中的应用.     

采用薄结构膜片的用于生物医学方面的高性能压阻式压力传感器

采用薄结构膜片的用于生物医学方面的高性能压阻式压力传感器Ｓ．Ｍａｒｃｏ，等１．引言高性能的硅压阻式压力传感器已广泛应用于工业环境中，然而在生物医学方面，若利用硅压阻式压力传感器进行介入性测量以直接监视被测物，则将在大小尺寸、准确度和灵敏度方面受到严格...     

有限元仿真在硅-蓝宝石高温压力传感器双膜片设计上的应用

本文介绍了在硅-蓝宝石高温压力传感器设计中,运用E型膜片弹性变形原理和传感器压阻效原理,对双E型膜片进行设计,为满足研制实际需求,采用ANSYS M echan ical模块对双膜片力学模型仿真分析,绘出膜片径向应力切向应力的线性分布,合理构建膜片结构的相关参数,将压阻元件布局在应力分布的最佳区域上,研制的传感器满量程输出≥100mV,线性度提高为≤0.01%,传感器精度0.1%。     

电磁传感器用磁-弹材料的研制

前言为了适应自动控制系统发展的需要,对于某些一直采用的压力传感器必须革新,这就是用电磁传感器来代替压力传感器。它具有比压力传感器体积大大缩小,重量大大减轻的特点,更重要的是它的灵敏度亦比压力传感器高。这种传感器的核心部份是一对对称的磁芯和一个膜片。磁芯和膜片组成一对磁通路,当压力或压差作用于膜片上时,膜片则     

Low Pressure Piezoresistive Sensors for Medical Electronics Applications

Piezoresistive pressure sensors are being widely used for various industrial applications, such as in automobiles and process control. But conventional MEMS piezoresistive pressure sensors possess low sensitivity in the lower pressure range for biomedical applications. Alternative structures of MEMS pressure sensors include the use of bossed diaphragms and nanocrystalline piezoresistors. In this paper, four different diaphragm structures—flat diaphragm, standard bossed diaphragm, complementary bossed diaphragm, and nanocrystalline porous silicon-silicon composite diaphragm—have been analyzed in terms of sensitivity and nonlinearity.     

MEMS-Capacitive Pressure Sensor Fabricated Using Printed-Circuit-Processing Techniques

Microelectromechanical systems (MEMS)-based capacitive pressure sensors are typically fabricated using silicon-micromachining techniques. In this paper, a novel liquid-crystal polymer (LCP)-based MEMS-capacitive pressure sensor, fabricated using printed-circuit-processing technique, is reported. The pressure sensor consists of a cylindrical cavity formed by a sandwich of an LCP substrate, an LCP spacer layer with circular holes, and an LCP top layer. The bottom electrode and the top electrode of the capacitive pressure sensor are defined on the top side of the LCP substrate and the bottom side of the top-LCP layer, respectively. An example pressure sensor with a diaphragm radius of 1.6 mm provides a total capacitance change of 0.277 pF for an applied pressure in the range of 0-100 kPa     

Molecule–Graphene Hybrid Materials with Tunable Mechanoresponse: Highly Sensitive Pressure Sensors for Health Monitoring

The development of pressure sensors is crucial for the implementation of electronic skins and for health monitoring integrated into novel wearable devices. Tremendous effort is devoted toward improving their sensitivity, e.g., by employing microstructured electrodes or active materials through cumbersome processes. Here, a radically new type of piezoresistive pressure sensor based on a millefeuille‐like architecture of reduced graphene oxide (rGO) intercalated by covalently tethered molecular pillars holding on‐demand mechanical properties are fabricated. By applying a tiny pressure to the multilayer structure, the electron tunnelling ruling the charge transport between successive rGO sheets yields a colossal decrease in the material's electrical resistance. Significantly, the intrinsic rigidity of the molecular pillars employed enables the fine‐tuning of the sensor's sensitivity, reaching sensitivities as high as 0.82 kPa^?1 in the low pressure region (0–0.6 kPa), with short response times (≈24 ms) and detection limit (7 Pa). The pressure sensors enable efficient heartbeat monitoring and can be easily transformed into a matrix capable of providing a 3D map of the pressure exerted by different objects.     

In-situ sugar-templated porous elastomer sensor with high sensitivity for wearables

Fabrication of elastic pressure sensors with low cost, high sensitivity, and mechanical durability is important for wearables, electronic skins and soft robotics. Here, we develop high-sensitivity porous elastomeric sensors for piezoresistive and capacitive pressure detection. Specifically, a porous polydimethylsiloxane (PDMS) sponge embedded with conductive fillers of carbon nanotubes (CNTs) or reduced graphene oxide (rGO) was fabricated by an in-situ sugar template strategy. The sensor demonstrates sensitive deformation to applied pressure, exhibiting large and fast response in resistance or capacitance for detection of a wide range of pressure (0‒5 kPa). PDMS, as a high-elasticity framework, enables creation of sensors with high sensitivity, excellent stability, and durability for long-term usage. The highest sensitivities of 22.1 and 68.3 kPa⁻¹ can be attained by devices with 5% CNTs and 4% rGO, respectively. The geometrics of the sponge sensor is tailorable using tableting technology for different applications. The sensors demonstrate finger motion detection and heart-rate monitoring in real-time, as well as a capacitive sensor array for identification of pressure and shape of placed objects, exhibiting good potential for wearables and human-machine interactions.     

Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring

Flexible pressure sensors have many potential applications in wearable electronics, robotics, health monitoring, and more. In particular, liquid‐metal‐based sensors are especially promising as they can undergo strains of over 200% without failure. However, current liquid‐metal‐based strain sensors are incapable of resolving small pressure changes in the few kPa range, making them unsuitable for applications such as heart‐rate monitoring, which require a much lower pressure detection resolution. In this paper, a microfluidic tactile diaphragm pressure sensor based on embedded Galinstan microchannels (70 µm width × 70 µm height) capable of resolving sub‐50 Pa changes in pressure with sub‐100 Pa detection limits and a response time of 90 ms is demonstrated. An embedded equivalent Wheatstone bridge circuit makes the most of tangential and radial strain fields, leading to high sensitivities of a 0.0835 kPa^?1 change in output voltage. The Wheatstone bridge also provides temperature self‐compensation, allowing for operation in the range of 20–50 °C. As examples of potential applications, a polydimethylsiloxane (PDMS) wristband with an embedded microfluidic diaphragm pressure sensor capable of real‐time pulse monitoring and a PDMS glove with multiple embedded sensors to provide comprehensive tactile feedback of a human hand when touching or holding objects are demonstrated.     

Study on the micro-heater geometry in In,2O3 micro electro mechanical systems gas sensor platforms and effects on NO2 gas detecting performances

Micro electro mechanical systems (MEMS) platforms for gas sensing devices with the co-planar type micro-heaters were designed, fabricated and its effects on the In2O3 gas sensors were investigated. Micro-heaters in MEMS gas sensor platforms were designed in the four-type heater patterns with different geometries. Electro-thermal characterizations showed that the designed platforms had highly thermal efficiency because the micro hot-plate structures were formed in the diaphragm and the thermal efficiencies were analyzed for all of 16 models and compared with each other, respectively. The designed micro-platforms were fabricated by MEMS process, and Indium oxide (In2O3) nanoparticles were synthesized by sol-gel process and dropped on the MEMS platforms for detecting the noxious oxide gas (NO2) Fabricated micro-platforms had a very low power consumption in the fabricated 16-type models, especially, the minimum power consumption was 41 mW at the operating temperature of 250 degrees C. After experiments on gas sensing characteristics to NO2 gases, fabricated In2O3 gas sensors had almost the same gas sensitivity (Rs) at the operation temperature of 250 degrees C. It is concluded that the micro-heater geometries, pattern shapes and sizes, can be influential on the power consumption of the devices and its gas sensing characteristics.     

基于分子印迹技术的尿素仿生微传感器

设计了基于分子印迹与电化学微传感器的尿素仿生微传感器,采用MEMS工艺制作集成微型3电极系统,实现了传感器的微型化.通过电化学方法制备了分子印迹聚合物(MIP),印证了分子印迹聚合物的印迹效果.比较了3支传感器的响应曲线,得到了相近的灵敏度,灵敏度在0.10μA/(μmol.L-1)左右,线性度达到了0.95,检测下限为1.00μmol/mL,分析尿素溶液的标准偏差小于5%,达到和接近临床分析要求,为生物传感器向仿生生物传感器发展进行了具有临床意义的尝试.     

印章特性和印刷压力对微接触印刷工艺的影响

微接触印刷（μCP）是一种能在微纳米尺度上完成表面图案化的技术,主要特点是高效和低成本．研究了μCP过程中印章机械特性和印刷压力对形成的微图案质量的影响．为了进一步分析聚二甲基硅氧烷（PDMS）制作的印章特性,浇注了5种配比的PDMS试样,并进行了单轴拉伸和压缩试验,获得了其应力应变关系．制作了3种配比的表面线型图案印章,实施微接触印刷使其印刷压强在1kPa～1MPa．通过图形化分析对最终的微接触印刷质量进行评估．实验结果表明：最优的压强区间为20～200kPa．较小的压力将会产生印章与基底的间隙,而较大的压力将会导致印章的严重变形．由于质量比为20：1的PDMS印章的弹性模量最小,其在中等压力下的微接触印刷质量最好,而较硬的印章可有效地抵抗印刷中产生的变形．     

MEMS矢量水听器声压通道封装技术研究

为了更全面地获取水下声场信息,微机电系统(Micro-Electro-Mechanical System,MEMS)矢量水听器常需集成声压敏感通道来提升单个换能器性能,MEMS矢量水听器的敏感芯片采用的是MEMS工艺制备完成,其封装必须与水隔离,传统的橡胶灌封方式会破坏MEMS敏感芯片的机电性能,故MEMS敏感芯片常采...     

Fabrication and testing of bulk micromachined silicon carbide piezoresistive pressure sensors for high temperature applications

This paper explores the development of high-temperature pressure sensors based on polycrystalline and single-crystalline 3C-SiC piezoresistors and fabricated by bulk micromachining the underlying 100-mm diameter (100) silicon substrate. In one embodiment, phosphorus-doped APCVD polycrystalline 3C-SiC (poly-SiC) was used for the piezoresistors and sensor diaphragm, with LPCVD silicon nitride employed to electrically isolate the piezoresistor from the diaphragm. These piezoresistors fabricated from poly-SiC films deposited at different temperatures and doping levels were characterized, showing -2.1 as the best gauge factor and exhibited a sensitivities up to 20.9-mV/V*psi at room temperature. In a second embodiment, epitaxially-grown unintentionally nitrogen-doped single-crystalline 3C-SiC piezoresistors were fabricated on silicon diaphragms, with thermally grown silicon dioxide employed for the piezoresistor electrical isolation from the diaphragm. The associated 3C-SiC/SiO/sub 2//Si substrate was fabricated by bonding a (100) silicon wafer carrying the 3C-SiC onto a silicon wafer with thermal oxide covering its surface. The 3C-SiC handle wafer was then etched away in KOH. The diaphragm was fabricated by time etching the silicon substrate. The sensors were tested at temperatures up to 400/spl deg/C and exhibited a sensitivity of 177.6-mV/V*psi at room temperature and 63.1-mV/V*psi at 400/spl deg/C. The estimated longitudinal gauge factor of 3C-SiC piezoresistors along the [100] direction was estimated at about -18 at room temperature and -7 at 400/spl deg/C.