基于MEMS技术的通信器件及其应用

微电子机械系统是一种新兴技术,它几乎影响着每一个科学技术领域,如交通、无线通信、航天、化学以及光波系统。目前许多工业领域期待选用微电子机械系统来解决技术上的问题。以下简述了微电子机械系统技术的基础概念、所用材料、加工工艺等;重点综述了基于MEMS技术的通信器件及其应。     

射频系统中MEMS谐振器和滤波器

介绍了目前国内外射频系统中所涉及的静电梳状谐振器、自由梁谐振器、薄膜声体波谐振器、腔结构谐振器、平行谐振器结构HF带通滤波器、折叠梁MF滤波器、分布传输线可调滤波器等MEMS谐振、滤波器件.对这些器件的结构原理、制造方法以及性能指标作了分析.把这些器件的性能指标和目前射频系统中谐振器、滤波器的性能要求进行比较,分析了这些器件的应用前景.最后,对基于MEMS技术的射频谐振器、滤波器发展作出展望.     

MEMS器件及其在生物医学上的应用

介绍了MEMS技术的发展概况及MEMS器件在信息领域、传感领域、生物技术领域的应用,重点介绍了MEMS在生物医疗中的应用及未来发展的趋势。     

High-density data acquisition system and signal preprocessor for interfacing with microelectromechanical system-based biosensor arrays

Microelectromechanical system (MEMS) development has become an active area for research in over the last decade. This area has advanced rapidly in recent years due to the potential ability of MEMS devices to perform complex functions in a smaller area. There is also the prospect to develop devices that can (1) be easily manufactured, (2) offer low power consumption, and (3) reduce waste. Especially in the BioMEMS area these advantages are important in terms of applied devices for biosensing, clinical diagnostics, physiological sensing, flow cytometry, and other lab-on-a-chip applications. However, one major obstacle that has been overlooked is the interface of these microdevices with the macroworld. This is critical to enable applications and development of the technology, as currently testing and analysis of data from these devices is mostly limited to generic microprobe stations. New advancements in BioMEMS have to occur in concert with the development of data acquisition systems and signal preprocessors to fully appreciate and test these developing technologies. In this work, we present the development of a cost effective, high throughput data acquisition system (Bio-HD DAQ) and a signal preprocessor for a MEMS-based cell electrophysiology lab-on-a-Chip (CEL-C) device. The signal preprocessor consists of a printed circuit board mounted with the CEL-C device and a 64-channel filter/amplifier circuit array. The data acquisition system includes a high-density crosspoint switching matrix that connects the signal preprocessor to a 16-channel, 18 bit, and 625 kSs DAQ card. Multimodule custom software designed on LABVIEW 7.0 is used to control the DAQ system. While this version of the Bio-HD DAQ system and accompanying software are designed keeping in view the specific requirements of the CEL-C device, it is highly adaptable and, with minor modifications, can become a generic data acquisition system for MEMS development, testing, and application.     

考虑接触热阻的高速列车制动盘热机耦合行为分析

接触界面间存在的接触热阻对制动盘内部热流传递过程有重要影响，进而影响制动盘热机耦合仿真分析的准确性。通过建立考虑接触热阻的有限元模型，结合制动台架试验，系统分析某高速列车轮装制动盘在紧急制动过程中的温度分布、盘面变形、螺栓载荷以及螺栓孔边应力等热机耦合行为。结果表明，选定的接触热阻模型得到的仿真结果与台架试验结果在较大的速度范围内吻合较好。制动系统内的温度梯度导致制动盘体产生较大的热应力并发生离面变形，是导致螺栓载荷增大的主要原因。制动盘面螺栓孔边沿制动盘半径方向的0°和180°位置附近的周向应力变化量较大，且处在较高的平均应力水平，是最容易产生制动热疲劳裂纹的两个方向。     

微制造的生物途径

介绍与论述了微制造工艺的发展方向和微制造的一种新途径-根据分子生物学原则，设计和合成或通过分子克隆制备生物聚合物，借助分子自组装实现微型机械或微系统的制造。     

MEMS技术及应用的新进展

MEMS是微电子和微机械的集成体 ,目前制备 MEMS的材料和工艺等得到很大发展 ,但其研究理论尚不成熟。本文综述了当前制备 MEMS的几个重要步骤 (即设计、材料选择、加工、封装以及测试 )的发展水平和存在问题 ;并总结了 MEMS应用的最新进展和未来前景     

Molecular lubricants for silicon‐based microelectromechanical systems (MEMS): a novel assembly strategy

Microelectromechanical systems (MEMS) are poised to bring the next technology revolution. At present, many of these are fabricated from silicon using lithographic techniques developed in the microelectronics industry. Due to the large surface area to volume ratio on the micrometer scale, surface forces, such as adhesion and friction, are often detrimental to the fabrication and operation of MEMS devices. Thus, one of the key issues in MEMS is surface engineering to reduce adhesion and friction. Here, we present a general strategy for the efficient assembly of organic layers directly onto the silicon surface in both vacuum environment and solution phases via the robust Si–N or Si–O linkage. This is achieved by the reaction between an amine or alcohol functional group and a chlorinated Si surface. The resulting surface assemblies are thermally stable. Characterization by interfacial force microscope (IFM) reveals that these assemblies have very low surface energy and are mechanically stable. This revised version was published online in September 2006 with corrections to the Cover Date.     

微机电系统的研究与展望

微机电系统(MEMS)是利用集成电路制造技术和微架构技术把微结构、微传感器、微执行器、控制处理电路甚至接口、通信和电源等制造在一块或多块芯片上的微型集成系统.MEMS技术是多种学科交叉融合具有战略意义的前沿技术.文中介绍了MEMS的范畴、分类、特点,综述了MEMS的发展历程和各国MEMS技术研发动态及产业现状,分析了M...     

面向微机电系统组装与封装的微操作装备关键技术

对微机电系统(Micro electro mechanical systems, MEMS)组装与封装工艺的特点进行了总结分析,给出了MEMS组装与封装设备的研究现状。针对MEMS产业发展的特点,分析了面向MEMS组装与封装的微操作设备中的工艺参数优化数据库、快速精密定位、模块化作业工具、快速显微视觉、柔性装夹和自动化物流等关键技术。在此基础上,详细介绍了研制的MEMS传感器阳极化键合设备和引线键合设备的组成结构、工作原理,并给出了组装和封装试验结果。最后,指出了MEMS组装与封装技术及设备研制的发展趋势。     

Good things, small packages [microelectromechanical systems]

While semiconductor chip manufacturers still suffer from the recent downturn, the future looks a little brighter for microelectromechanical systems (MEMS). Also called microsystems and micromachines, these devices are found in many diverse applications, such as air bag sensors, ink-jet heads, medical sensors and telecommunication switches. MEMS can be manufactured from a variety of materials using a variety of processes in a variety of steps. For the foundry industries, it creates problems because each process can only be used for one customer. Because of their application-specific nature, MEMS devices often have to be designed using proprietary manufacturing processes that are specific to one manufacturing facility. In this paper, the author examined the surrounding issues in manufacturing MEMS as well as the probable solutions hypothesized by different experts.     

Failure Mechanisms of Capacitive MEMS RF Switch Contacts

Microelectromechanical systems (MEMS) radio frequency (RF) switches hold great promise in a myriad of commercial, aerospace, and military applications. In particular, capacitive type switches with metal-to-dielectric contacts (typically Au- on-silicon nitride) are suitable for high frequency (≥10 GHz) applications. However, there is little fundamental understanding of the factors determining the performance and reliability of these devices. To address this void in understanding, we conducted fundamental studies of Au-on-Si₃N₄ contacts at various bias voltages using a micro/nanoadhesion apparatus as a switch simulator. The experiments were conducted in air at 45% relative humidity. The switch simulator allows us to measure fundamental parameters such as contact force and adhesion, which cannot be directly measured with actual MEMS switches. Adhesion was found to be the primary failure mechanism. Both a mechanical and electrical effect contributed to high adhesion. The mechanical effect is adhesion growth with cycling due to surface smoothening, which allows increased van der Waals interaction. The electrical effect on adhesion is due to electrostatic force associated with excess charge trapped in the dielectric, and was only observed at 40 V bias and above. The two effects are additive, but the electrical effect was not present until surfaces were worn smooth by cycling. Surface smoothening increases the electric field in the dielectric, which leads to trapped charge and higher adhesion. Excessive adhesion can explain decreased lifetime at high bias voltage previously reported with actual capacitive MEMS switches. Aging of open contacts in air was found to reduce adhesion. Surface analysis data show the presence and growth (in air) of an adventitious film containing carbon and oxygen. The adventitious film is responsible for aging related adhesion reduction by increasing surface separation and/or reducing surface energy. No junction growth and force relaxation with time were observed in capacitive switch contacts, as was previously observed with Au–Au contacts at low current in direct current MEMS switches.     

Calculating the effective material constant for multigrain orthotropic polysilicon by the boundary element method

The reliability and safety of MEMS parts are important factors in industrial MEMS applications. Most MEMS parts are made from multigrain polysilicon, an orthotropic material with random material direction. Analyzing the stress and displacement and knowing the effective material constant are important when using MEMS in industrial applications. We developed a computer program to calculate the effective material constant of polysilicon using the boundary element method with the microstructure evolution method. The results obtained using the boundary element method were compared to those obtained using the finite element method to confirm the validity of the program.     

面向工程振动环境监测需求的MEMS加速度计及其应用

要:随着我国重大建设项目的日益增多,核电设施、大型桥梁、大科学装置等重要建筑工程对其所处环境的振动控制要求愈发苛刻,对工程振动的监测需求也日益强烈.基于硅微加工和超精密制造的MEMS加速度计集成度更高、尺寸更小、功耗和成本更低,高度契合需要使用极多加速度计的振动环境监测的应用需求.文中介绍了压电式和电容式MEMS加速度...     

A web-enabled open database system for design and manufacturing of micro-electro-mechanical systems (MEMS)

This paper presents the development of a web-enabled database system for MEMS design and manufacturing which can provide the networked design and manufacturing services over the Internet. Specifically, the data obtained from various sources for MEMS manufacturing processes/materials are organised as databases by using the relational database management systems (RDBMS), Microsoft Access and MySQL. The database system can be accessed from a Java application as well as an applet. The stand-alone Java application is created using JFC Swing, JDBC and SQL, and the Java applet is subsequently created to enable web functionality. The underlying database is open, extensible through a set of administrator tools or via the web, which gives commercial design and manufacturing facilities the ability to update their own materials, processes and rules. This plays a crucial role in the system for advisory MEMS manufacturing service and concurrent collaborative MEMS design and simulation. The developed database system, e-MEMS Designer @Database, which contains extensive manufacturing or fabrication processes and materials databases for MEMS and microelectronics, is easily incorporated as a sub-system into both the standalone system and the web-enabled MEMS design system, MEMS Designer, which is being developed. The database system can also be updated to create a comprehensive data warehouse and an advisory system for MEMS manufacturing processes/materials selection.     

隧道掘进机大数据研究进展：数据挖掘助推隧道挖掘

随着传感与智能化技术不断发展，隧道掘进机的运行监测日趋完善，所记录的海量实测数据不仅包含了装备作业过程的重要信息，也蕴含了装备内部及其与外部环境的相互作用机理，通过一定方法对这些数据进行深度挖掘与分析对于提升装备设计、分析、运行与维护水平具有十分重要的意义。为总结和分析隧道掘进机实测数据研究方法与应用状况，首先概述隧道掘进机实测数据的来源、构成与特点，从数据驱动的装备状态识别与性能预测、地质识别与地表改变预测、隧道健康监测与预警三个方面综述国内外相关文献，总结和归纳当前研究的难点、优点与不足，最后从隧道掘进机实测数据预处理方法、多源异构数据建模方法、模型泛化能力提升方法、数据计算平台等方面对未来研究方向进行初步分析与展望，为后续隧道掘进机大数据研究提供参考与借鉴。     

电控摩擦技术的研究进展

作为一种主动控制摩擦性能技术,电控摩擦技术可解决实际中的电接触摩擦问题和主动控制摩擦副的摩擦与磨损性能。综述电控摩擦技术的研究进展,介绍该领域已形成大量的理论体系,如自生电势、表面转移膜、化学反应膜等,展望电控摩擦技术的发展方向。微型化是机电系统的发展趋势,同时也是电控摩擦技术的研究趋势;在微机电系统或纳米机电系统领域,微电控摩擦技术或纳米电控摩擦技术有很好的应用前景。     

微型机械的特点,研究现状和应用

简明地叙述了微型机构的特点,综述了微型机构在国内外的研究现状,强调了微型马达的研究在微型机械发展中的重要地位,列举了微型机械应用的典型实例,最后对我国在九五期间发展微型机械提出了一些建议。     

激光直写制造石墨烯基柔性电子器件的研究进展

柔性电子器件相对于传统电子器件,拥有独特的柔性和延展性,能够在一定程度上适应不同的工作环境,满足设备的形变需求。石墨烯是开发柔性电子器件的理想材料。然而,传统的石墨烯加工技术大多涉及高温和化学溶剂,存在着成本高,工艺线路复杂和环境污染等问题,并不适合未来产业发展。激光直写（Laser direct writing,LDW）技术具有加工速度快,扫描面积大和空间分辨率高等优点,且无需掩模和后处理,在现代工业中广泛应用。最新研究表明,激光直写技术可以从氧化石墨烯、多种聚合物甚至天然材料中衍生出石墨烯,这无疑进一步提升了石墨烯基柔性电子器件的应用潜力。本文对现有激光直写技术制备石墨烯的前驱体进行了归纳分类,并详细介绍了相应的演变过程、加工原理及辅助加工设备,总结了基底转印、表面应变结构、剪纸拓扑结构这三种常见的柔性化制造策略,并重点阐述了其在超级电容器、传感器、纳米发电机和致动器等石墨烯基柔性电子器件中的最新应用,最后对其发展趋势及挑战进行讨论。     

Finite element analysis of nanostructures with roughness and scratches

Finite element analysis facilitates optimal design of MEMS/NEMS devices for reliability. A finite element method (FEM) was developed to analyze the effect of types of surface roughness and scratches on stresses of nanostructures. Beams with surface roughness in the form of semicircular and grooved asperities in varying numbers in the longitudinal direction were considered. In the transverse direction semicircular asperities and scratches in varying numbers and with different pitch were modeled. Furthermore semicircular asperities were truncated both in longitudinal and transverse direction and analyzed. It was observed that the asperities and scratches increase the bending tensile stresses which could lead to failure of MEMS/NEMS devices. The beam material was assumed to be purely elastic, elastic-plastic and elastic-perfectly plastic to observe the variations in the bending stresses and displacements for both smooth nanobeam and nanobeam with defined roughness. The results of the analysis can be useful to designers to develop the most suitable geometry for nanostructures.