一种半岛型结构谐振梁压力传感器

提出了一种新型结构压力传感器 ,器件由上下两硅片键合而成 ,上硅片制作半岛型结构氮化硅谐振梁 ,下硅片制作矩形压力膜。应用有限元软件对器件结构及灵敏度进行了计算机模拟分析 ,器件利用MEMS技术研制并采用电热激励压阻拾振方式进行了测试。实验及理论模拟分析结果证实新型结构可以大大提高压力传感器灵敏度     

一种半岛型结构谐振梁压力传感器

提出了一种新型结构压力传感器,器件由上下两硅片键合而成,上硅片制作半岛型结构氮化硅谐振梁,下硅片制作矩形压力膜.应用有限元软件对器件结构及灵敏度进行了计算机模拟分析,器件利用MEMS技术研制并采用电热激励压阻拾振方式进行了测试.实验及理论模拟分析结果证实新型结构可以大大提高压力传感器灵敏度.     

高精度MEMS硅谐振压力传感器闭环控制系统

硅谐振压力传感器因其数字频率信号输出和高精度的特点,被广泛应用于航空航天、工业控制等领域。硅谐振压力传感器的闭环控制系统决定硅谐振压力传感器的性能指标,系统的稳定性分析和参数优化则是谐振传感器的研究难点。基于系统状态方程从理论上推导了控制策略,提出系统稳定性判定依据。利用Simulink仿真搭建系统模型,并通过电路测试验证。结果表明,在满足稳定性判据的条件下,研制的硅谐振压力传感器基频为42 kHz,品质因数为30 000。在量程范围为3～130 kPa、温度为-55～85℃时,该谐振压力传感器的精度高达0.01%F.S.,实现了恒幅控制与实时频率跟踪。     

热激励硅谐振梁压力传感器开环测试系统设计

设计了一个开环测试系统,利用锁相放大器能够对微弱信号进行有效检测的特点,采用交流激励、二倍频拾振的方法,实现了对热激励硅谐振梁压力传感器谐振输出的微弱信号的检测。该测试系统能够快速测得传感器的幅频特性曲线;通过处理,得到传感器的压力-频率特性。整个测试过程由程序控制实现。     

谐振梁压力传感器的气密封装技术

文章介绍了谐振粱压力传感器的气密封装技术，全面分析了影响气密封装的各种因素，提出了相应的解决方法。     

热激励硅基双梁谐振型压力传感器

针对热激励硅基谐振型压力传感器温度漂移严重的问题,提出了一种双梁硅基谐振型压力传感器结构,利用不测试压力的谐振梁感应温度对谐振梁的变化,并与测试压力的谐振梁相减,消除测试压力的谐振梁随温度变化的部分,补偿热激励硅基谐振型压力传感器的温度漂移.通过实验,研制出双梁结构的硅基谐振型压力传感器样品,初步测试结果显示,温度漂移的影响已降低到原来的1/30,大大提高了热激励硅基谐振型压力传感器的测试精度.     

静电刚度式谐振微加速度传感器的结构稳定性

为了研究静电刚度式谐振微加速度传感器结构稳定的判据和影响其稳定性的因素,根据静电刚度式谐振微加速度传感器的结构原理,分析了传感器中质量块与音叉梁的运动和受力特点,建立了传感器中质量块与音叉梁在加速度作用前后的力平衡方程。采用数值方法求解力平衡方程,得到了传感器结构的一个稳定平衡点和一个非稳定平衡点,以及两个平衡点重合时对应的结构稳定临界检测电压,分析了加速度作用前后不同质量块支撑梁弹性系数和平行板检测电容间隙对临界检测电压的影响。结果显示,临界检测电压随质量快支撑梁弹性系数和平行板检测电容间隙的增大而增加。当有加速度作用时,临界检测电压将发生变化,但对量程为-1~1g的超低量程加速度传感器,加速度作用前后临界检测电压变化很小,不会引起传感器结构稳定性太大的变化。     

MEMS硅梁谐振式传感器的研究

通过对硅梁谐振式传感器工作原理的研究,结合Intellisuite软件对硅微悬臂梁谐振器的振动特性进行了分析,设计了具有悬臂梁结构的电热激励/压阻拾振的谐振式传感器,这种传感器具有体积小、功耗低、灵敏度高、准数字信号输出、成本低、与集成电路工艺兼容等优点。对研究制作过程中的关键工艺——各向异性腐蚀技术,尤其是对低温下的腐蚀工艺进行了实验研究,采用高低温相结合的湿法腐蚀工艺制作了微悬臂梁结构,通过实验分析了利用新型有机薄膜对各向异性腐蚀过程中的MEMS器件金属电极的保护效果,为实际生产和设计提供了参考依据。     

一种基于谐振原理的微型压力传感器设计

设计了一种结构简单的微型石英谐振式压力传感器,该传感器芯片由力学转换元件、谐振敏感元件和支撑元件3部分构成。仿真分析了压力100kPa内传感器输出频率与输入压力的关系,经线性拟合后得出其最大相对非线性误差为0.09%。采用石英深槽湿法腐蚀的方法加工出了芯片3个元件结构,并经镀膜及键合等后工序制作出了传感器芯片,其性能实测值与仿真结果基本吻合,验证了结构及工艺方案的可行性。     

一种新型真空微电子压力传感器的研制

采用各向异性腐蚀与各向同性腐蚀相结合的技术和特殊的硅-硅键合技术,成功地研制出了一种新型真空微电子压力传感器。测试分析结果表明,该传感器反向击穿电压达到100V;在加3V正向电压时,其单个锥尖发射电流为0.2nA;在25-100g的压力范围内与输出电压呈线性关系,灵敏度为0.1μA/g。     

Optically excited resonant beam pressure sensor

Micromechanical silicon beams fabricated by anisotropic etching techniques are coated with a thin layer of chromium. An intensity-modulated laser beam focused on the beam generates transverse vibrations which are detected interferometrically. In the letter we report how the vibration frequency changes with temperature and pressure applied to the beam.     

A relocatable resonant FBG-acoustic emission sensor with strain-insensitive structure

A novel resonant fiber Bragg grating （FBG） based acoustic emission （AE） sensor with relocatable, strain-insensitive and enhanced sensitivity structure is demonstrated for structure health monitoring （SHM） in this paper. With one end of the sensing FBG bonded to a polyimide （PI） plate acoustically the other end free, the sensor can be easily redeployed around coupled with the investigated structure via couplant and the monitored structure surface and get rid of the interference from the strain applied on the monitored structure. Experiment has been conducted to verify the characteristics of this FBG-AE sensor, whose results show that the sensor is insensitive to mechanical strain applied on the monitored structure. It is also shown experimentally that the sensitivity is enhanced by about 1.2 times than the conventiotlal design, while the novel sensor possesses good resonant frequency response to the standard AE waves.     

Novel optically excited resonant pressure sensor

A novel pressure sensitive microresonator structure has been fabricated by anisotropic etching of silicon. An intensity modulated laser beam is focused onto the resonator and generates transverse vibrations, which are detected using optical heterodyne interferometric techniques. The pressure and temperature dependence of the resonant frequency of this structure is reported     

Optically excited resonant diaphragm pressure sensor

Silicon diaphragms fabricated by anisotropic etching are coated with a thin layer of aluminium. An intensitymodulated laser beam focused on the diphragm generates transverse vibrations which are detected interferometrically. Differential pressure is applied to the diaphragm and the pressure-induced change in the fundamental resonant frequency is reported.     

基于L型悬臂梁的膜片式FBG压力传感器

为满足油气管道压力测量需求,本文提出并研究 了一种使用膜片和L型悬臂梁作为压力转换单元的 光纤布拉格光栅(FBG)压力传感器。基于传感器的结构模型,通过理论计算对传感器灵敏 度和温度自补 偿效应进行了分析,并利用有限元法分析了传感器的静态和动态特性。实验结果表明,在0－2MPa范 围内,该传感器的压力灵敏度为1185.621pm/M Pa,相关系数达到 0.999,在0－80 ℃温 度范围内温 度灵敏度相关系数达到0.999以上,能有效消除温度交叉敏感。且具 有良好的可靠性,这种FBG压力传感器可广泛用于油气管道压力的长期准分布在线监测。     

A remote pressure sensor with digital signal interface

A high performance pressure sensor circuit is described with a digital signal interface for accurate remote sensing of pressure. The signal conditioning circuitry converts sensor resistance variation into a digital signal. Automatic offset error correction prevents long term and temperature drift effects on overall performance. The digitized signal is detected remotely over two wires by means of optical or ferrite coupling. The same two wires were used for power supply delivery. Floating operation allows good performance in a noisy environment. Test results have shown less than 0-25 psi/°C input equivalent pressure error in a temperature range of – 25°C to +75°C. The non-linearity was less than 0-2% in a dynamic pressure range of 500/1 at room temperature.     

A monolithic capacitive pressure sensor with pulse-period output

A new microminiature monolithic capacitive pressure transducer (CPT I) is 20 times more sensitive than piezoresistive strain-gauge pressure transducers, requires one percent of the power, and can be batch fabricated through current integrated circuit technology. A second device (CPT II) incorporates bipolar signal-processing electronics on the same silicon chip to produce a low-duty-cycle pulse-mode output with period related to pressure. This output format helps to re-solve the problem of shunting between leads, which is one of the principal causes of long-term drift in piezoresistive transducers designed for implantable medical applications. Because this device uses capacitance change as a transductional mechanism rather than piezo-resistivity, it is not susceptible to drift caused by temperature variations in the piezoresistive coefficient. Optimization for totally implantable biomedical applications places special emphasis on small size, high sensitivity, improved long-term baseline stability, and greatly reduced power consumption. These properties are also important for a wide range of pressure-sensing applications-from automotive to general industrial use.     

Finite-element model-based fault diagnosis, a case study of a ceramic pressure sensor structure

Finite-element (FE) analysis is an efficient aid in the design optimisation of modern electronic devices. Simulation tools have dramatically reduced the product design cycle. The model validated with actual prototypes can also be used for other purposes such as failure analysis, fatigue prediction, reliability studies, etc. In this paper we present a case study of application of FE model in fault localisation in ceramic pressure sensor structures. The sensing elements are thick-film resistors acting as strain gauges, which translate the strain into an electrical signal. In the design phase, FE analysis was used to analyse the sensitivity of the thick-film resistors to the applied pressure. The same model was used for non-destructive fault diagnosis and troubleshooting of the prototype series. Selected examples illustrate the approach. FE model can also be used in the production test process. Since simulations are rather time consuming, quick fault localisation can be performed by a fault dictionary while in-depth diagnosis is performed by FE analysis.     

A new structure for a fingertip force sensor

Presents a structural design for force/torque fingertip sensors to sense planar forces. Not only can the resolution be increased by reducing the condition number of the calibration matrix, but also the accuracy can be enhanced by a precise and simple calibration method. Moreover, the theoretical analysis and design procedure of the proposed structure are included in this paper, and experimental results demonstrate the proposed design