圆片级叠层键合技术在SOI高温压力传感器中的应用

针对绝缘体上硅(SOI)异质异构结构特点,提出了两次对准和两次阳极键合工艺方法,实现了圆片级SOI高温压力传感器硅敏感芯片的叠层键合。采用玻璃—硅—玻璃三层结构的SOI压力芯片具有良好的密封性和键合强度。经测试结果表明:SOI高温压力传感器芯片键合界面均匀平整无缺陷,漏率低于5×10~(-9)Pa·m~3/s,键合强度大于3 MPa。对芯片进行无引线封装,在500℃下测试得出传感器总精度小于0. 5%FS。     

A simple thermo-compression bonding setup for wire bonding interconnection in pressure sensor silicon chip packaging

In the process of piezo-resistive pressure sensor packaging, a simple thermo-compression bonding setup has been fabricated to achieve the wire bonding interconnection of a silicon chip with printed circuit board. An annealed gold wire is joined onto a pad surface with a needle-like chisel under a force of 0.5–1.5 N/point. The temperature of the substrate was maintained in the range of 150–200°C and the temperature of the chisel was fixed at around 150°C during wire bonding operation. The tensile strength of the wire bonding was measured with a bonding tester by the destructive-pulling experiment and was found to be at the average of 132 mN/mm². The microstructure of the bonding point was examined by scanning electron microscopy. The interface of the thermo-compression boning was shown to possess an acceptable level of reliability for a micro-electromechanical system (MEMS)-based device. The results showed that this setup can be easily operated for fabrication and is suitable for fabricating not only low-cost pressure sensors, but also other MEMS devices.

     

A simple thermo-compression bonding setup for wire bonding interconnection in pressure sensor silicon chip packaging

In the process of piezo-resistive pressure sensor packaging, a simple thermo-compression bonding setup has been fabricated to achieve the wire bonding interconnection of a silicon chip with printed circuit board. An annealed gold wire is joined onto a pad surface with a needle-like chisel under a force of 0.5?C1.5?N/point. The temperature of the substrate was maintained in the range of 150?C200°C and the temperature of the chisel was fixed at around 150°C during wire bonding operation. The tensile strength of the wire bonding was measured with a bonding tester by the destructive-pulling experiment and was found to be at the average of 132?mN/mm². The microstructure of the bonding point was examined by scanning electron microscopy. The interface of the thermo-compression boning was shown to possess an acceptable level of reliability for a micro-electromechanical system (MEMS)-based device. The results showed that this setup can be easily operated for fabrication and is suitable for fabricating not only low-cost pressure sensors, but also other MEMS devices.     

SOI压力传感器的灵敏度优化设计

目前压阻式压力传感器灵敏度优化计算仅基于压阻条整体性几何分布,在相关参数的优化上存在局限性,且在模型及计算等方面有一定误差.本文提出一种专门用于SOI压力传感器,通过精确分析敏感栅的栅数、栅长以及其坐标分布的最佳组合参数,结合不同量程芯体膜厚的计算,达到传感器灵敏度优化的方法.基于Microsoft Visual C++平台以及有限元、数值分析等接口技术,采用参数化建模,有限元分析仿真,数值后处理,编制循环分析算法,设计SOI压力传感器灵敏度优化程序.通过实验数据验证优化设计与实际吻合较好.     

氧化铝陶瓷基无线无源压力传感器的高温性能研究

利用高温烧结陶瓷技术制备了一种基于氧化铝陶瓷的LC谐振式无线无源压力传感器,并通过合理地设计圆柱螺旋天线以及隔热结构,实现了该传感器在高温环境中的无线耦合测试。研究了传感器在不同温度下的阻抗频率特性,分析并探讨了传感器的高温性能。测试结果表明,在29℃(室温)至700℃的温度范围内,测试天线端的最高瞬时温度为188.4℃,保证了传感器高温测试的可靠性。谐振频率对温度的平均变化量为1.314 kHz/℃,两次重复性测试的相对变化量为3.81%,重复性较好。该压力传感器可应用于高温恶劣环境下的压力测试,其高温性能的研究为压力信号的准确读取奠定了良好的基础。     

Condition based maintenance of the two-beam laser welding in high volume manufacturing of piezoelectric pressure sensor

Two-beam laser welding (TBLW) is an advanced process for precise, low distortion joining of cylindrical miniature parts. The process is composed of a laser source, optics and various actuators, which form a sophisticated system for control and maintenance in high volume manufacturing. A well-established method for identifying welding defects and ensuring welding quality is the monitoring of plasma light emission in TBLW. Although such monitoring systems can detect a change in process status, they are not able to diagnose the nature of the fault. The main challenge in this research was to extend the use of quality-based monitoring systems to measure additional deterioration-related parameters and to estimate system deterioration from them by using expert knowledge.This paper shows a novel condition-based maintenance (CBM) for the TBLW system, which performs condition identification using online monitoring of plasma light emission in combination with offline inspection of the seam macrographs. A combination of quality parameters derived from seam macrographs of defective parts is used to identify process deterioration, such as contamination of the optics, misalignment of the optomechanical system, or reduced laser power. The information obtained is used to make predefined process adjustments based on expert domain knowledge. The implementation of the developed CBM in high volume manufacturing of piezoelectric pressure sensors resulted in more predictable TBLW by reducing system failures as well as shorter diagnosis times.     

基于正交试验的光纤传感器金属化连接工艺优化

为了克服光纤传感器有机胶封装带来的可靠性差、应变传递效率低的问题,采用粒子扩散系统对光纤传感器进行金属化连接以实现光纤传感器的无胶封装;为提高金属粘接层与基体的结合强度,设计了以工作距离、驱动电压、进给速度、粒子场气压为试验素的4水平正交试验方案,并用划痕法对金属粘接层的结合强度结果进行评估。通过统计分析,获得了影响金属粘接层与基体结合强度的主要因素和次要因素,优化了光纤传感器金属化连接工艺。     

电涡流汽车空调压力传感器弹性元件的优化设计

针对汽车空调压力线性测量的要求,分析了现有产品及相关成果,提出了电涡流测量方案;设计了集被测体、电感线圈和处理电路为一体,独立的电涡流汽车空调压力传感器的弹性元件;继而分析了弹性元件的结构、工艺和材料,并从理论计算、有限元分析两个方面对弹性元件的工作状态进行计算、模拟;最后实验测得该传感器传感器具有很高的灵敏度(151mV/0.1MPa)和线性度,从而验证了设计的合理性和正确性.     

A hybrid capacitive pressure and temperature sensor fabricated by adhesive bonding technique for harsh environment of kraft pulp digesters

We have developed a compensated capacitive pressure and temperature sensor for kraft pulp digesters (pH 13.5, temperatures 25–175°C reaching a local maximum of 180°C and pressures up to 2 MPa). The gauge capacitive pressure sensor was fabricated by bonding silicon and Pyrex chips using a high temperature, low viscosity UV (ultraviolent) adhesive as the gap-controlling layer and heat curing adhesive as the bonding agent. A simple chip bonding technique, involving insertion of the adhesive into the gap between two chips was developed. A platinum thin-film wire was patterned on top of a silicon chip to form a resistance temperature detector (RTD) with a nominal resistance of 1,500 Ω. A silicon dioxide layer and a thin layer of Parylene were deposited to passivate the pressure sensor diaphragm and the sensors were embedded into epoxy for protection against the caustic environment in kraft digesters. The sensors were tested up to 2 MPa and 170°C in an environment chamber. The maximum thermal error of ±1% (absolute value of ±20 kPa) full scale output (FSO) and an average sensitivity of 0.554 fF/kPa were measured. Parylene-coated silicon chips were tested for a full kraft pulping cycle with no signs of corrosion.     

Role of laser sensor systems in automation and flexible manufacturing

New industries and production plants require a flexible system, which is capable of picking up objects of various shapes, weights, and colors with arbitrary position and orientation. Such a system also needs recognition and guiding sub-systems. The recognition system includes target function for the recognition sub-system and relation between object characteristics and recognition target. The laser sensor system can be used for such object recognition. Wire-based telemetry and control systems can cause many problems in shop floors and factories, and so there has been a strong growth of interest in wireless guidance like vehicles equipped with laser guiding and navigation systems. For the continuous measurements of parameters such as temperature, etc. optical laser sensor technology seems to become more applicable at this stage. This article describes the operational principles and the use of the most advanced laser sensor systems for quantity measurements, guiding, navigation, pattern recognition, and vision systems for inspection purposes. A variety of laser-based sensors, which can be used as sensing devices in manufacturing, and production technology, are described in this study. Adaptive cruise control systems that can be used in automobile industry to monitor distance and speed are described in this report. As a typical example, the principal operation of a laser guided mobile robot using a laser navigation system is also described.     

膜盒式压力传感器的应用

介绍了远距离冷气压力表传感器和指示器的基本构造及二者的电路连接关系 ,利用简单的电路实现了远距离冷气压力的测量。详细论述了远距离冷气压力表的测压原理。     

压阻式压力传感器在无人机上的应用

主要介绍了压阻式压力传感器的特点及在无人机上用其来解算高度、速度等参数的使用情况 ,经过温度补偿后 ,使传感器的温度特性得到了进一步的改善 ,用单片机解算高度、速度 ,达到了满意的效果 ,同时分析了压阻式传感器的应用前景     

各向异性磁电阻传感器Barber电极的优化设计

利用ANSYS软件对各向异性磁电阻(AMR)传感器不同取向的Barber电极进行分析和计算,得到不同取向Barber电极的磁电阻相对变化率随归一化磁场的变化曲线,从而为改善具有Barber电极的AMR传感器输出曲线的对称性、优化AMR传感器的输出特性提供了理论依据。     

压力传感器检测系统的研制

在 - 6 0～ 85℃的温度范围内 ,压力传感器检测系统可以满足压力传感器静态特性参数的检测 ,它采用了液体传压原理、温度控制技术和计算机应用技术。解决了压力传感器的热零点漂移、热灵敏度漂移、非线性、迟滞和重复性在不同温度环境条件下难以精确检测的问题 ,为压力传感器的研究和使用提供依据 ,在压力传感器研制和生产中有着重要的应用价值。     

高温压力传感器的温度补偿

介绍了高温压力传感器热零点漂移产生的原因以及一种抑制漂移的补偿办法 ,即利用相关材料的线膨胀系数的不同进行补偿。     

Coverage area enhancement in wireless sensor network

In the wireless sensor network, coverage area may be enhanced after an initial deployment of sensors. Though, some research works propose how to decrease the coverage hole by increasing sensing range or movement assisted sensor deployment, these are not suitable for energy constraint wireless sensor network, as longer mobility distance or higher power level consume more energy. In this paper, we address the increasing coverage area through smaller mobility of nodes. We find out the coverage hole in the monitoring region, which is not covering by any sensing disk of sensor. Then, we address the new position of mobility nodes to increase the coverage area. The simulation result shows the mobile nodes can recover the coverage hole perfectly. The coverage holes is recovered by mobility on the existing recovery area, which cannot be lost. Moreover, hole detection time in our proposed protocol is better than existing algorithm.

     

石英晶体谐振式绝对压力传感器研制

介绍了一体化石英谐振式压力传感器的研制,采用石英晶体材料制做弹性膜片,用音叉式石英力敏谐振器检测压力,减少了传感器的体积,降低了制造工艺难度。研制的传感器量程为0~120 kPa,中心频率为(40±4)kHz,精度为0.05%。     

液态金属压力传感器感压元件设计

设计了一种应用于液态金属压力测量的差动变压器式压力传感器,介绍了传感器的工作原理和设计方案,着重介绍了波纹管复合弹簧机构(即感压元件)的结构设计和仿真计算,为传感器的设计开发提供了理论基础.该传感器具有灵敏度高、分辨力大等特点,特别适合环境恶劣、介质复杂、工作温度高的条件下对压力的测量.     

引压方式动态压力传感器研制

介绍了一种通过引压方式探测动态压力信号的传感器。由于受到被测介质温度高和被测环境空间尺寸小限制,传感器需要通过引压管传递动态工作压力。为了保证引压管在传递动态压力过程中不影响传感器的频响特性,设计了一种阻抗匹配结构,减小了引压结构对传感器动态响应特性的影响,保证了动压传感器的频响特性,该传感器的检测单元包括一个引压管、一个敏感元件、一个电路组件、一个阻抗匹配管。测试结果表明：动压传感器具有（31.5～8000 Hz）频响范围。