利用JEET压阻效应设计硅杯的原理

本文给出了利用JEET压阻效应设计C型硅杯的结构,分析了JEET的压阻效应,使电流性压力灵敏度可达2.5％/10~6dyn/cm~2,提出了一种有良好工作稳定性和噪声性能的力学量敏感器件——JEET力敏器件。     

硅—兰宝石集成力敏器件的研究

一、引言硅—兰宝石集成力敏器件是在硅压阻型力敏器件基础之上发展起来的一种新型的无结固态压阻型力敏器件。和硅集成力敏器件相比,具有时间稳定性好、耐高温、抗辐射和耐腐蚀等优点,因此它一出现就倍受人们重视。然而,由于硅—兰宝石集成力敏器件出现的时间不长,有关它的设计、制做等目前尚缺乏必要的理论基础和实验依据。本文通过对硅—兰宝石集成力敏器件整个研制过程的总结,对其设计、制做等关键环节予以较详尽的阐述,寄希望本文能对我国硅—兰宝     

硅杯同轴度的检测

文中介绍了扩散硅力敏传感器的核心元件硅杯的同轴度检测的几种方法。     

硅电容传感器中静电封接工艺技术的应用

对于新近发展起来的新一代结构型力敏器件,如硅电容力敏器件、电容型加速度力敏器件等,常规的静电封接工艺已无法满足其小间隙(间隙通常小于10 μm)封接的特殊要求,封接后会造成极板间的粘连,导致器件失效.文中结合电容传感器的结构特点,提出了一种小间隙,非粘连的静电封接工艺方法,确定了相应的封接温度、封接电压、封接时间的选择原则,论述了容性器件封接中的相关问题.该工艺已成功地应用于硅电容传感器的制作中,效果良好,对于结构型力敏器件的制作具有较强的实用价值.     

EI型扩散硅力敏器件工艺技术研究

本文叙述的EI型扩散硅力敏器件为工业变送器配套使用的微差压传感器，其压力量程为0．6kPa，线性优于0．5％。该器件填补国内空白，器件性能指标达到国际80年代中期同类产品先进水平。     

低热机械噪声的梳齿式加速度计

文中介绍了一种基于低噪声梳齿变面积型加速度计.采用体硅加工工艺,利用SOI材料30 μm顶层硅制造垂直梳齿,梳齿数目达200对,提高了初始电容,能够充分利用尺寸空间,获得具有低噪特性的加速度计.该种形式的加速度计不需要真空封装,也不需要制作阻尼孔就能满足低噪声要求.器件采用三层材料,利用硅-玻璃键合和BCB键合实现,能够有效提高成品率,并给出了成功流片后得到的SEM照片.最后,对器件进行了频谱响应曲线的测试,测试得到器件在非真空封装及无阻尼孔情况下Q值高达156.95.测试结果表明该器件的设计简化了制造工艺,降低了成本,同时得到提高了Q值,能够降低热机械噪声.     

利用有限元分析工具优化设计微气体传感器结构

利用金属铂的热阻、热敏特性以及SiO2、SiNx良好的绝热绝缘特性，设计一种以金属铂薄层为加热器，叉指状金薄层为信号电极，SiO2和SiNx为隔热和电绝缘层的硅基微结构气敏元件。利用有限元分析工具ANSYS，对该硅基微结构气敏元件的加热衬底的温度场进行模拟和分析，根据分析的结果对所设计的气敏元件优化，优化后的气敏元件热损耗将更小，响应速度将更快。     

硅微压传感元件的设计分析及关键技术

本文介绍了圆形膜片E型杯硅微压传感元件的设计原理。并针对硅微压传感元件研制中存在的问题，提出采用化学腐蚀技术，选择性腐蚀工艺控制膜厚。用E型杯代替C型杯的设计，改善非线性误差获得成功。研制出量程≤kPa，精度优于0．5％的微压元件。     

一种CMOS磁敏传感器

一、前言为将磁敏感结构作为硅传统集成电路的一部分集成起来,发展了一种集成电路。它们一般用作位置传感器(如用在键盘、机床电机上等),磁电极,交流/直流电流传感器等。第一个磁敏MOS器件是由Gallagher和Corak发明的MOS霍尔元件。这种器件可以获得10~3V/AT的灵敏度。由Fry和Hoey设计的一种对漏MOS晶体管电路可     

下期要目预告

·SG-75扩散硅压力传感器·超声波铁路车辆滑滚轴承识别装置的·光纤声发射传感器 研究·电涡流传感器设计·应用于电容传感技术的新电路·力敏器件中间测试装置加载工作台的·高精度压力综合放大器设计 设计·一种移动式焦炉火道的自动测温装置下期要目预告     

基于MEMS技术的金属应变式压力传感器优化设计

文中从金属应变式压力传感器的基本理论出发,以硅弹性膜铂应变电阻压力传感器为原型,推导了圆形和方形弹性膜片上电阻的变化率(dR/R)公式。通过比较,选用方形弹性膜为压力承压膜,以优化承压膜的宽厚比为出发点,用有限元方法对不同厚度方形膜片(宽度为2 mm)进行应力分析。由硅材料的屈服应力与最大位移的限制,确定了最优的膜厚范围;根据有限元仿真的结果对压力传感器进行优化设计,对所做压力传感器芯片进行测试,在6.00×104~1.06×105Pa的范围内,其精度优于50 Pa.     

A complementary-metal-oxide-semiconductor-field-effect-transistor-compatible atomic force microscopy tip fabrication process and integrated atomic force microscopy cantilevers fabricated with this process

A complementary-metal-oxide-semiconductor-field-effect-transistor-compatible process for the fabrication of atomic force microscopy cantilevers with integrated tips has been developed. For the first time, the tips are fabricated after the completion of the regular complementary metal-oxide-semiconductor-field-effect-transistor fabrication process sequence. On-chip circuit components, such as piezoresistive deflection sensors, deflection actuators, and amplifiers, are fabricated on the mirror-polished surface of the wafer, ensuring optimal performance. The tip fabrication process is based on anisotropic silicon etching at low temperature using a tetramethylammonium hydroxide solution. The anisotropic etching process has been optimized to ensure process controllability. Using the described process, complementary-metal-oxide-semiconductor-field-effect-transistor-based cantilevers with piezoresistive deflection sensors and integrated tips have been successfully fabricated. Force-distance curves and scanning images in constant-force mode have been recorded.     

扩散硅力敏器件CAD技术的研究：结构应力分析

本文介绍在ＩＢＭ系列及其兼容系列微型机上，实现硅压力传感器中硅杯结构的应力分析方法和软件。该软件对微机软件、硬件资源的要求很低，能对包括工艺误差在内的各种复杂的硅杯结构绘出准确的应力分析图。     

The design of blank’s initial shape in the near net-shape deep drawing of square cup

Deep drawing process is very useful in industrial field because of its efficiency. The deep drawing is affected by many process variables, such as blank shapes, profile radii of punch and die, formability of materials and so on. Especially, in order to obtain the optimal products in deep drawing process, blank shape is very important formability factor. In this paper, the finite element method is used to investigate the cup height of the square cup drawing process. In order to verify the prediction of FEM simulation of the product’s height and forming load in the square cup drawing process, the experimental data are compared with the results of the current simulation. A finite element analysis is also utilized to acquire the designed profile of the drawn products, a reverse forming method for obtaining the initial blank’s shape according to the forward square cup drawing simulation is proposed. The design of initial blank’s shape is also certified to obtain the designed profile of drawn cups by experiment. The influences of the blank’s shape on the height of product, the forming load, the maximum effective stress and the maximum effective strain are also examined.     

Nanofriction of silicon oxide surfaces covered with thin water films

A thin water film present on surfaces plays a central role in defining the micro- and nanotribological properties of a system. This paper presents a quantitative examination of the nanotribological effects of thin water films in ultra high vacuum (UHV) on OH-terminated (hydrophilic) and bare (no OH terminations, hydrophobic in vacuum) silicon oxide surfaces. Water film thickness was controlled by varying the water partial pressure in UHV. Friction was measured by scanning force microscopy (SFM) as a function of an external applied load. The surface energy and the shear stress of the nanotribological contact was then approximated by fitting the friction-load curves using the Derjaguin-Muller-Toporov (DMT) model. The surface energy as well as the adhesion force of the OH-terminated hydrophilic sample first decrease and later increase significantly at higher water partial pressures. No such dependence could be deduced from the friction-load curves at varying water pressures for the bare hydrophobic silicon oxide surface. However, at relatively high normal loads (pressures) and water partial pressures the bare hydrophobic silicon oxide is transformed to an OH-terminated surface. This transformation appears to occur only in the area of contact leading to the conclusion that it is friction-induced. This work shows that the chemical composition of the topmost surface layer defines the frictional behavior of the tribosystem.     

E型扩散硅力敏器件的研制

本文阐述了Ｅ型膜片的结构特性，根据其应力分布特点及硅材料在（１１０）晶面的＜１１１＞晶向上具有最大压阻系数，开展了力敏芯片的最佳设计，并进行了Ｅ型力敏器件的制作。最后给出了器件的主要技术指标。     

圆筒形件拉深失稳及各因素影响分析

对板料成形中圆筒形件拉深的破裂失稳及产生破裂失稳的临界压边力进行研究.由于凸、凹模圆角及其间隙的存在,圆筒形件拉深的筒壁区实际为凸、凹模圆角之间的公切线部分.根据Mises-Hill屈服函数及Tresca准则求出凸缘变形区、凹模圆角区和筒壁区的应力分布,得到危险断面处的应力表达式,从而求出不产生破裂失稳的临界压边力的解析表达式,并进一步分析获得拉深比、硬化指数、厚向异性系数、摩擦因数以及径向推力等因素对临界压边力的影响规律.采用液压压边与周缘加径向推力的拉深模具对08Al板料进行拉深试验,试验结果与理论计算结果具有很好的一致性.     

筒形件多次拉深极限预测

依据再次拉深筒坯口部最厚、最硬,以及最大拉深力出现于拉深后期的特点,假定最大拉深力相应于筒口达到变形区入口位置,采用平衡微分方程和塑性方程联解方法,建立了变形区应力数值解。应用分散性失稳准则,导出再拉深危险断面失稳强度。利用再拉深极限理论及首次拉深极限理论［1］,通过计算机可以迅速准确地预测筒形件及带实缘筒形件的多次极限拉深系数。     

差厚激光拼焊板盒形件的数值模拟研究

拼焊板技术在汽车制造业中得到了广泛的应用。焊缝存在是拼焊板成形性能降低的一个重要因素,因此研究控制焊缝移动非常重要。通过对盒形件拉伸的应力分析,得到焊缝移动规律;基于非线性隐式算法,选用各向异性屈服准则,采用阶梯压边圈,精确建立了焊缝模型,对盒形件拉深进行了数值模拟,并与试验结果进行了比较。通过对模拟结果的应力、单元厚度分析,比较模拟和试验的吻合程度,验证了应力分析和模拟的正确性。     

An Analysis of Draw-Wall Wrinkling in a Stamping Die Design

Wrinkling that occurs in the stamping of tapered square cups and stepped rectangular cups is investigated. A common characteristic of these two types of wrinkling is that the wrinkles are found at the draw wall that is relatively unsup-ported. In the stamping of a tapered square cup, the effect of process parameters, such as the die gap and blank-holder force, on the occurrence of wrinkling is examined using finite-element simulations. The simulation results show that the larger the die gap, the more severe is the wrinkling, and such wrinkling cannot be suppressed by increasing the blank-holder force. In the analysis of wrinkling that occurred in the stamping of a stepped rectangular cup, an actual production part that has a similar type of geometry was examined. The wrinkles found at the draw wall are attributed to the unbalanced stretching of the sheet metal between the punch head and the step edge. An optimum die design for the purpose of eliminating the wrinkles is determined using finite-element analysis. The good agreement between the simulation results and those observed in the wrinkle-free production part validates the accuracy of the finite-element analysis, and demonstrates the advantage of using finite-element analysis for stamping die design.