多晶硅横向压阻灵敏度的统计分析

本文用统计方法对择优生长的多晶硅横向压阻进行了分析:计算了<100>、<110>、<111>、<211>、<221>、<311>、<331>等低指数晶向择优生长的P型和N型多晶硅横向平均晶粒压阻系数;采用全空间统计平均的方法,计算得到了晶向完全随机的多晶硅横向平均晶粒压阻系数;从欧姆定律和多晶硅晶粒特性出发,推导了多晶硅横向压阻灵敏度的表达式。通过实验测量了多晶硅横向压阻器件的灵敏度及其与角度的关系,证实多晶硅横向压阻灵敏度与器件倾角α符合sin2α的关系。将实验结果与理论分析的结果相比较后,得到了多晶硅的杨氏模量,这些结果表明多晶硅横向压力传感器具有实用价值,并为器件提供了优化的设计方案。     

用硅压阻式压力传感器解算高度速度的方法

简要阐述了解算气压高度速度的原理，对使用硅压阻式压力传感器来解算高度速度的误差和传感器选择作了详细分析，结果表明，用硅压阻式压力传感器来作简易的高度速度测量，可达到中等测量精度的水平。     

高精度硅压阻式气压计设计

针对硅压阻式气压传感器因温漂、离散性大而使其应用受限的问题,设计了一种高精度硅压阻式数字气压计。该气压计采用全温度范围的曲面拟合算法进行温度补偿和线性化处理,解决了硅压阻式气压传感器的温漂和非线性问题;在ATmega88PA微控制器内采用软件实现压力数据的温度补偿,并通过RS485接口将数据发送给上位机。测试结果表明,在-40～+60℃范围内,该气压计测量误差在0.50‰以内,满足设计要求。     

一种冲击加速度传感器的研究

本文介绍一种周边固支圆形膜片硅压阻式冲击加速度计的工作原理和结构,以及硅膜片尺寸与传感器输出的计算关系,冲击加速度传感器的电阻设计,及其器件的制作工艺流程。通过冲击试验,证明了该加速度传感器在高加速度作用下的实用性。     

基于切割成型的侧壁表面压阻制作及其参数优化

为了提高MEMS执行器件对面内运动位移（或力学信号）检测的灵敏度并改善侧壁检测电阻制作工艺与其他工艺及其不同器件结构之间的兼容性问题,提出一种基于离子注入工艺和深度反应离子刻蚀（DRIE）工艺相结合制作检测梁侧壁压阻的方法。在此基础上,详细分析了影响位移检测灵敏度和分辨率的各种因素,并对侧壁压阻的结构尺寸及其工艺参数进行优化。最后,给出了侧壁表面压阻在几种不同类型典型MEMS执行器件中的应用,取得了很好的应用效果。     

高精度硅压阻式气压传感器系统设计

为了消除环境温度对硅压阻式传感器输出的影响,大幅提升硅压阻式传感器的测量精度,将传感器芯片与热源和测温原件封装在一起,通过控制加热的方式使传感器工作在恒定50℃的环境中,对传感器进行线性标定和测试.结果显示:在-45～45℃环境下,600～1 100 hPa量程内气压传感器的测量误差小于0.3 hPa.     

压阻式压力传感器性能的研究

微压力传感器是微机电领域最早开始研究并且实用化的器件之一,它结构简单、用途广泛。本文介绍了基于压阻效应及惠斯顿电桥的压阻式压力传感器。介绍了膜的面积、厚度、电阻形状和位置等参数对压阻式压力传感器的灵敏度和线性度的影响。     

URS型压阻式深度计

URS型压阻式深度计,是液位测量领域中的新型仪表,具有结构紧凑、安装方便、测量准确和灵敏度高等特点。该深度计测量头可直接投入被测液体中,借助于不同水深的压力变化测量水位。传感器为扩散硅压阻器件,无机械可动部件,且不受周围电场、磁场及气候条件的影响,这使之优越于目前各种类型的液位检测仪表。该深度计属国外80年代初的新型仪表,目前德国WIKA公司、美国阿克美特公司都有同类     

精密压阻弹性体及力敏触觉传感器阵列

空气热氧化用多元醇溶剂热方法得到的金属钌纳米颗粒,可以得到纳米氧化钌颗粒,将其与金属钌纳米粉体混合,使其具有适当的聚集特性,将混合粉体与硅橡胶复合,呈现具有良好的压阻重复性和压阻敏感性,测量不同尺寸电极间的压阻行为,表明此种导电硅橡胶在毫米尺寸以上呈现一定的标度不变性,表明材料在一定尺寸范围内满足微型化要求,适用于集成的压阻弹性体应力测量阵列,我们制备了测量面载荷分布的阵列电极,设计了用于动态触觉传感测量的电路和支持软件,结果表明,针对压阻材料电阻/载荷敏感特性,通过每个压阻单元微秒级的信号获取和数据处理,可以实现毫米尺度的静态或动态载荷三维成像,该传感阵列的可重复和定量特性使其基本满足实用的人体工学器件要求。     

一种高灵敏度硅微机械陀螺的设计与制造

设计与制造了一种高灵敏度的硅微机械陀螺。陀螺用静电来驱动,用连接成惠斯顿电桥的压阻式力敏电阻应变计来检测。主梁、微梁 质量块结构实现了高灵敏度。比较硬的主梁提供了一定的机械强度,并且提供了高共振频率。微梁很细,检测时微梁沿轴向直拉直压。力敏电阻应变计就扩散在微梁上,质量块很小的挠动就能在微梁上产生很大的应力,输出很大的信号。5V条件下,陀螺检测部分的理论灵敏度达到27.45mV/gn。压阻式四端器件用来监测驱动振幅,可以反馈补偿压阻的温度系数。检测模态的Q值达260使陀螺能在大气下工作。陀螺利用普通的n型硅片制造,为了刻蚀高深宽比的结构,使用了深反应离子刻蚀(DRIE)工艺。     

400MPa压阻式压力传感器

采用高强度合金膜片作为初始敏感元件来承受被测压力，再利用硅油将压力传递到压阻敏感元件上，经硅油传递后的压力要比被测压力小很多，从而可用低量程的压阻元件制成超高压力传感器。基于此原理，本文采用量程为２ＭＰａ的压阻元件，研制成了４００ＭＰａ量程的超高压力传感器。     

The mechanics of polymer swelling on microcantilever sensors

This paper investigates the swelling mechanics of polymer capture layers integrated into piezoresistive cantilever biochemical sensors. A finite element model investigates mechanical deformations in a polymer layer affixed to a silicon microcantilever. The polymer swells during analyte absorption, inducing deformations in the silicon cantilever which are sensed by a piezoresistive sensor integrated into the cantilever. The highest sensitivity is predicted for short and wide cantilevers that are coated with stiff polymer whose thickness is twice that of the cantilever. While the polymer swelling induces the deformations, the silicon carries most of the load. When portions of the silicon beam are removed to introduce stress concentrations, the system sensitivity can increase by 18% compared to the cantilever without stress concentrations. This study of stress distributions in the cantilever system allows sensor optimization that considers the full 3D effects of polymer swelling mechanics.     

Influence of polycrystalline silicon as electrical shield on reliability and stability of piezoresistive sensors

In this paper, the influence of polycrystalline silicon as a protective field shield on the reliability and stability of piezoresistive silicon sensors is investigated. For this purpose, the behaviour of piezoresistive sensors with and without polycrystalline silicon shield is observed under changes of environmental condition, such as relative humidity and temperature. The obtained sensor-offset change under humidity stimulation is smaller than that observed by temperature excitation. The samples with polycrystalline silicon shield exhibit a lower humidity and temperature coefficients as compared to the samples without this shield. The values of uncertainties in measurement are evaluated according to the ISO “Guide to the Expression of Uncertainties in Measurement” (GUM). The uncertainty contribution caused by internal disturbing of the sensors can be neglected. Comparing two types of piezoresistive sensors investigated, the samples with polycrystalline silicon shield produce a considerably reduction of all measurement uncertainty contributions. The results show that an additional polycrystalline silicon shield between two insulating layers connected to the supply voltage, which provides a determined potential distribution inside the passivation layer stack, improves the device reliability and the accuracy of measurement.     

A new micromachined sensor system for tactile measurements of high aspect ratio microstructures

A new tactile sensor with piezoresistive read-out is presented. The sensor is designed for measurements of high aspect ratio structures with a resolution of some 10 nm and a measuring range of hundreds of micrometer. Possible applications of the sensor are suggested. The silicon micromachining fabrication process is shown in detail next to the finite element simulations we performed. First measurements and a calibration process are described and the results are shown. The implementation into a measuring system is indicated.     

基于PSO的BP神经网络在压力传感器温度补偿中的应用

针对硅压阻式压力传感器的温度漂移问题,提出了基于粒子群优化算法PSO(Particle Swarm Optimization Algorithm)的BP神经网络的温度补偿模型,通过粒子群化算法对BP网络的权值和阈值进行全局寻优,克服了BP网络收敛速度慢和易陷入局部极值的缺陷,而且温度补偿的精度较高。研究结果表明,该方法有效的抑制了温度对压力传感器输出的影响,提高了传感器的稳定性和准确性。     

基于SOI技术梁膜结合高过载压阻式加速度计研究

采用微型机械电子系统技术和集成电路工艺制作出了SOI技术高灵敏度的硅微固态压阻平膜芯片;通过动力学分析和有限元模拟,研制出了具有高过载保护功能的加速度传感器结构;通过玻璃粉烧结工艺将其键合在弹性梁的应力集中处,研制出量程为±2000 g、过载能力为30倍满量程的高过载梁膜结合压阻式加速度计.加速度计具有较高的测量灵敏度和精度,满量程输出为126.97 mV/2V,静态精度为0.86%FS.     

纳机电探针阵列与压阻式传感器集成技术研究

给出了纳机电探针阵列与压阻式传感器集成一维阵列器件结构及工作原理;通过理论计算得到该结构的一些主要的特性参数,计算结果与ANSYS模拟结果相符合;并运用微纳机械加工技术制造出该器件。该器件将加热电阻器、压阻式传感器和硅基针尖集成于在同一超薄微细悬臂梁,通过楔形开孔的机械切断,避免了加热电阻器高温处的PN结在高温下失去电隔离作用。室温下测得该器件加热电阻器的阻值为500～600Ω,压阻式传感器的力敏电阻器的阻值为6～8kΩ。     

多路硅压阻式压力传感器温度补偿系统的设计与实现

基于MAX1457实现了一种多路硅压阻式压力传感器温度补偿系统.MAX1457是一种专用传感器信号调理芯片.此芯片集成化程度较高,可以补偿硅压阻式压力传感器的温度误差和非线性误差.经调理后的综合误差不超过0.1%.在分析该芯片补偿原理的基础上,设计并实现了一种多路补偿系统.     

Design principles and considerations for the ‘ideal’ silicon piezoresistive pressure sensor: a focused review

Over the past four decades, the field of silicon piezoresistive pressure sensors has undergone a major revolution in terms of design methodology and fabrication processes. Cutting edge fabrication technologies have resulted in improved precision in key factors like dimensions of diaphragm and placement of piezoresistors. Considering the unique nature of each sensor and the trade-offs in design, it is not feasible to follow a standard design approach. Thus, it is useful to derive the specific design from a number of important factors to arrive at the ‘ideal’ design. In this paper, we critically review and analyze the various design considerations and principles for silicon piezoresistive pressure sensor. We also report the effect of these considerations on the sensor output taking help of various CAD tools. Keeping in view the accuracy of state-of-the-art fabrication tools and the stringent demands of the present day market, it has become important to include many of these design aspects. Modelling using analytical expressions for thin plates has also been looked into as it gives a quick guideline and estimation of critical parameters before detailed finite element method analysis. Wherever possible, fabrication imperfections and their effects have been discussed. Dependency of piezoresistive coefficients on temperature and doping concentration, the effect of clamping condition of diaphragms and fabrication using wet bulk micromachining is also analyzed. Silicon-on-insulator based sensors along with innovative design strategies, and future trends have also been discussed. This paper will serve as a quick and comprehensive guide for pressure sensor developers.