硅基热流式微流量传感器研究

采用微电子技术和微机械加工技术,在硅衬底上设计制作了集微型加热器和温度传感器于一体的热流式微流量传感器.在恒功率的工作模式下,分析了微流量传感器的特性曲线.实验结果表明,硅基热流式微流量传感器的测量范围在10～800 μL/min之间.     

集成微流体测控芯片的研制

设计、研制了集成有微泵、微沟道、微流量传感器、温度传感器的微流体测控芯片.采用有限元软件ANSYS模拟分析了将其作为冷却芯片时微沟道的散热作用,分析确定了芯片上各元件的结构.该集成芯片为硅-玻璃结构,在硅片上,利用ICP法刻蚀无阀微泵泵体和微沟道;在7740玻璃片上,以溅射、剥离法制作微流量和温度传感器;图形精确对准后硅/玻璃以静电键合方法封接.无阀微泵采用压电元件驱动.测试结果表明:集成芯片具有冷却功能,循环水的流速最大可达25.4mm/s.     

用于低温环境的铂电阻温度微传感器

目前,铂电阻温度传感器主要应用于73 K(-200℃)以上环境的温度检测。设计了可用于10 K(-263℃)～200 K(-73℃)低温区的铂电阻温度微传感器。铂电阻温度微传感器采用对称的折回型结构,这种结构有效地降低了交流感抗的影响。传感器的敏感薄膜是一层采用磁控直流溅射沉积厚度为200 nm的铂薄膜。采用QD PPMS仪器测试传感器的电阻与温度的变化关系,得出传感器的电阻温度系数(TCR):研制的温度传感器的电阻温度系数在温度高于30K(-243℃)时可达到9980×10-6/K,同时在低于30K(-243℃)的深低温区域TCR也可达到3730×10-6/K。     

硅岛式微谐振压力传感器灵敏度分析与仿真

微谐振式压力传感器尺寸小、重量轻、精度高并具有效字输出,在航空航天等领域有着广阔的应用前景.然而由于微机械加工工艺的限制,复杂结构的制作存在很多困难,因而为实现高灵敏度压力测量,微谐振式压力传感器的结构设计就显得尤为重要,因此提出一种新型硅岛式谐振梁支撑结构,它利用硅薄膜作为典型的一次敏感元件,并在其上表面中央部位设计了两个硅岛凸起平台,用以固定硅谐振梁,并通过有限元软件ANSYS进行仿真.分析结果表明,在一定量程内,该结构能有效提高谐振梁内的应力放大倍数,进而提高微压力传感器的灵敏度.     

微型风速风向传感器研制

阐述了微型风速风向传感器的工作原理,结构设计及工艺研究,该传感器采用硅微机械加工技术制成微悬桥结构,将加热电阻器与感温电阻器排布在悬桥上,降低了功耗,提高了传感器灵敏度,实现低风速风场测量。     

一种硅微多传感器集成研究

为满足小体积、多参数测量的要求,利用(100)晶面的各向异性压阻特性与MEMS加工工艺特性,在单芯片上集成制作了三轴加速度、绝对压力以及温度等硅微传感器,在结构和检测电路设计上最大限度地减小各传感器之间的相互干扰影响。三轴加速度、绝对压力传感器利用压阻效应导致的电阻变化测量外界加速度和压力变化量,温度传感器利用掺杂单晶硅电阻率随温度变化的原理来测量外界温度。集成传感器具有较好的工艺兼容性,加速度、压力传感器的压敏电阻和温度传感器的测温电阻采用硼离子掺杂制作,加速度和压力传感器设计成工艺兼容的体硅结构。研制的集成传感器芯片尺寸为4mm×6mm×0.9mm。给出了集成传感器的性能测试结果。     

硅微机械结构的微电流型电化学气体传感器

探索研究了用于构制以硅为基体材料、具有特定三维微结构的微电流型电化学气体传感器的微加工工艺，提出了双面光刻、高硼掺杂腐蚀止停、化学各向异性刻蚀和硅表面多层膜剥离成形等既实用而又相容的硅微机械加工关键技术。如此构制的微电流型电化学气体传感器，在器件结构、检测灵敏度、电流响应的稳定重现性等方面，与用传统工艺制成的常规电流型气体传感器相比，具有独特的优点。     

MEMS应变式结冰传感器设计与制作

提出了一种MEMS应变式结冰传感器.传感器基于结冰造成薄膜刚度改变的原理,采用惠斯通电桥结构检测结冰薄膜上应变电阻的变化,感知结冰信号.传感器利用惠斯通电桥自身结构及外加温度补偿电路,可有效地抑制输出信号的温漂.通过理论分析和有限元仿真,分析了器件的敏感机理,并对结构参数进行计算.采用与IC工艺兼容的体硅MEMS工艺完...     

高性能SOI基纳米硅薄膜微压阻式压力传感器的研究

针对高端领域对高性能微小量程压力传感器的迫切需求，设计并实现了一种应用于电子血压计的高性能SOI基纳米硅薄膜微压阻式压力传感器，并提出了相应的检测电路。根据小挠度弯曲理论设计了传感器方形敏感薄膜结构，确定了纳米硅薄膜压敏电阻的阻值大小和尺寸。采用ANSYS有限元分析（FEA）对所设计的传感器结构进行仿真，根据仿真结果确定了压敏电阻在膜片上的最佳放置位置。基于标准MEMS制造技术，在SOI基纳米硅薄膜上设计并实现了该压力传感器。实测结果表明，室温下，在0～40 kPa微压测量范围内所设计的传感器检测灵敏度可达0.45 mV/（kPa·V），非线性度达到0.108%F.S。在-40℃～125℃的工作温度范围内，温度稳定性好，零点温度漂移系数与灵敏度温度漂移系数分别为0.004 7%F.S与0.089%F.S。所设计的压力传感器及其检测电路，在现代医疗、工业控制等领域具有较大的应用潜力。     

一种基于感声波纹结构的光学式声传感器

设计了一种基于硅MEMS敏感结构的光学式声传感器,其光学调制原理采用强度调制型,微敏感结构采用具有低应力波纹结构的感声薄膜芯片。对光纤与微敏感结构耦合技术进行实验研究,优化光学参数,并制作传感器样品。经实验测试,灵敏度达80mV/Pa。     

Mechanical characterization of post-buckled micro-bridge beams by micro-tensile testing

A micro-tensile testing system has been developed to measure the mechanical properties of post-buckled silicon dioxide micro-bridge beams. A kind of vernier-groove carrier is presented to improve alignment precision and repeatability of the measurement, and the stiffness coefficient of the tensile system is calibrated in situ in order to obtain the deformation of the tensile beams. Through analyzing a series of stress states in the beam over film preparation, post-buckling and unfolding of the beam, the initial residual stress in the film is obtained from the original load–displacement curves. The residual stress of 354 MPa is consistent with that calculated from the theory of finite deflection of buckled beams. Young’s modulus and tensile fracture strength are also obtained from the load–displacement curves. The measured modulus and strength are 64.6 ± 3 GPa and 332–489 MPa respectively. The measured properties of the thermal silicon dioxide film are reasonably coherent with other reports.     

ANSYS在热释电薄膜红外探测器二维热分析中的应用

根据热释电薄膜红外探测器的结构和实际的测试条件,利用有限元软件ANSYS建立了不同结构组成的热释电薄膜红外探测器的二维模型,并对其进行了热分析,得到了探测器内的温度场分布.分析了复合热释电薄膜红外探测器的绝热层对温度场的影响,并将复合热释电薄膜红外探测器与微桥结构探测器的性能进行了比较.     

Characterization of layer-by-layer nano self-assembled carbon nanotube/polymer film sensor for ethanol gas sensing properties

This paper reported a multi-wall carbon nanotubes (MWNTs)/polymer film-based sensor for ethanol gas detection. The film sensor was fabricated using layer-by-layer self-assembly method on the substrate with interdigital electrodes structure. The surface morphology of the self-assembled membranes shows a high strength, dense and random network structures, and the electrical properties of MWNTs/polymer film sensor were investigated. Its ethanol gas-sensing properties with varying gas concentration are characterized at room temperature. The experiment results shown that carboxylic groups attached on the MWNTs surface and the expansion of polyelectrolyte interlayer lead to a prompt response and sensitive resistance change when the sensor exposed to ethanol gas, indicating the unique advantages of layer-by-layer self-assembly of MWNTs/polymer film sensors in prospective application.     

Toward Flexible Thermoelectric Flow Sensors: A New Technological Approach

A new technological approach on thin flexible sensors is presented. As proof of concept, a thermoelectric flow sensor on a 10-mum-thick polyimide foil has been realized. The advantages of silicon as a thermoelectric material and the stability of low-pressure chemical vapor deposition (LPCVD)-silicon nitride as a protective coating are combined with the flexibility of polymer substrates. The thermoelectric flow sensor is fabricated on a standard silicon wafer for handling purposes. Only the functional layers that are embedded in 600 nm of LPCVD-silicon nitride are transferred onto a 10-mum-thick polyimide. The bulk silicon has been removed using deep reactive ion etching. Samples have been fabricated and tested, proving the potential of this new technological concept. The first characterization results show that the sensor layout has to be adapted to the properties of the polymer substrate.     

聚苯胺-多壁碳纳米管薄膜SAW NO2传感器

将聚苯胺-多壁碳纳米管聚合物沉积于声表面波(SAW)气体传感器的敏感区,形成敏感薄膜,实现了室温下对不同体积分数NO2的检测.研究表明:这种传感器具有很高的敏感性,良好的重复性和低体积分数检测极限.同时,单一聚苯胺薄膜也做了对比测量,实验结果表明:聚苯胺-多壁碳纳米管聚合物敏感膜比单一聚苯胺薄膜具有更高的敏感性和更短的...     

Detection of ethanol and methanol vapors using polymer-coated piezoresistive Si bridge

A novel alcohol vapor sensor based on the swelling effect of polymer film is proposed for detection of alcohol such as methanol and ethanol vapor, which is composed of a Si bridge embedded with piezoresistive Wheatstone bridge and an epoxy acrylate thin polymer layer-coated Si bridge. When the polymer layer absorbs alcohol vapor molecules from ambient air, the swelling of the thin polymer layer leads to bending of the Si bridge which causes the piezoresistive Wheatstone bridge to produce an output voltage. A theoretical model of the interaction between Si bridge and polymer layer is presented based on elastic mechanics theory. An equivalent transverse gas load is presented. The output expression of sensor is obtained. The model of the sensor is verified by the experimental results. The experimental results show that the alcohol vapor sensor has good linearity, selectivity and reproducibility. The proposed alcohol vapor sensor has simply principle, mature technology, low cost, and can be integrated with signal processing circuit using the MEMS processes.     

多晶硅高温压力传感器的芯片内温度补偿!

提出了一种新的改善传感器温度特性的方法.通过在压力传感器芯片上集成多晶硅电阻网络与温度传感器,借助传感器信号处理单元,可以方便地实现对灵敏度系数的补偿.经过补偿,传感器的零点温漂达到1×10-4/℃,灵敏度温漂低于-2×10-4/℃.这种方法补偿的温区宽,具有很强的通用性,使高温压力传感器十分有效的温度补偿方法.     

集成硅颜色传感器

介绍了一种新型的颜色传感器,其分光采用染色的聚酰亚胺滤色膜,它与传统的硅集成工艺兼容;敏感器件采用三个硅光二极管阵列。该传感器对入射光波长在380nm～650nm的范围内具有较高的灵敏度,且温漂小。     

Object imaging with a piezoelectric robotic tactile sensor

A two-dimensional, electrically multiplexed robotic tactile sensor was realized by coupling a piezoelectric polyvinylidene fluoride (PVDF) polymer film to a monolithic silicon integrated circuit (IC). The IC incorporates 64 sensor electrodes arranged in a symmetrical 8×8 matrix. Each electrode occupies a 400×400 μm square area, and they are separated from each other by 300 μm. A 40-μm-thick piezoelectric PVDF polymer film was attached to the electrode array with an electrically nonconductive methane adhesive. The response of the tactile sensor is linear for loads spanning 0.8-135 grams-of-force (gmf) (0.00-1.35 Newtons (N)). The response bandwidth is 25 Hz, the hysteresis level is tolerable, and, for operation in the sensor's linear range, taxel crosstalk is negligible. The historically persistent stability and response reproducibility limitation associated with piezoelectric-based tactile sensors has been solved by implementing a novel pre-charge voltage bias technique to initialize the pre- and post-load sensor responses. A rudimentary tactile object image measurement procedure for applied loads has been devised to recognize the silhouette of a sharp edge, square, trapezoid, isosceles triangle, circle, toroid, slotted screw, and cross-slotted screw     

新型温湿敏集成传感器研制

本文介绍了一种新的湿敏薄膜材料Ta_2O_5和一种新的硅衬底材料SOI/SDB的制备技术及它们的特性,给出了包含P-N结温敏元件的FET湿度的传感器结构及其特点.