多芯片组件技术的发展及应用

多芯片组件技术（MCM）是现代组装技术的新概念,它的出现促进了SMT（表面贴装技术）与SMD（表面贴装元器件）的发展和革新,并将成为高密度、高性能、多功能封装的最佳选择。     

微波多芯片组件中的微连接

实现微波多芯片组件(MCM)电气互连的微连接技术是MCM组介绍微连接的三种基本方式丝焊键合、凸点倒装和载带贴装,侧重介绍了各连接方式的优势和连接形式并进行了分析.     

MCM技术在DC／DC转换器中的应用

本文主要阐述了MCM技术与传统分立式元件表面贴装技术相比所具有的优势,并着重介绍了DrMOS在DC／DC转换器中的应用。     

表面贴装技术手工操作工艺

依据表面贴装技术(SMT)工业生产流程、SMT设备原理、表面贴装工程品质要求,提出了简便易行的表面贴装技术手工操作工艺方案,用SMT焊接技术来分析其工艺流程及工艺参数.介绍了表面贴装技术的工艺原理、工艺过程、手工操作方法及其特点,提供了表面贴装技术手工操作设备的配置、设计制作及使用方法,对印刷焊膏、表面贴装器件(SMD)贴装、回流焊接温度控制等关键工序提出了相应的品质要求和注意点,并对常见的焊接缺陷作了简单分析,解决了印制焊膏、贴装元器件、焊接、清洗、检测、返修等SMT焊接技术.     

显示术语面面观

SMD(surface mount de-vices)表面贴装器件没有引线,其焊端和引脚制作在同一平面内,并适用于表面组装技术的各种形状的电子元器件。它又称表面组装器件或表面组装元器件。其体积可以做得很小,组装密度很大。它是表面贴装技术(SurfaceMount Technology,SMT)元器件中的一种。除此之外还有表面组装元件(Surface Mountedcomponents,SMC)。SMC主要有矩形片式元件、圆柱形片式元件、复合片式元件、异形片式元件。SMD元件主要有片式晶体管和集成电路,集成电路又包括SOP、SOJ、PLCC、LCCC、QFP、BGA、CSP、FC、MCM等。     

MCM/BGA走向主流

高性能电子的目标是为了达到最小的连线长度而把各个组装器件密集在一起。为了达到这种高密度的要求,多芯片模块层压板(MCM/L或MCM-L)技术将提供最好的机遇和可能以满足这个目标。MCM产品的设计包括了要仔细地选择管芯(die)和基板表面的管理,从而把SMDs贴装到MCM线路板的一面或两面上。但是COB和TAB组装仅以一面来进行。     

SMD技术向高端的发展趋势

引言 电子整机在小型化、便携式、多功能、数字化以及高可靠、高性能方面的需求,进一步推动表面贴装型元器件(SMD)技术向集成化迅速发展。原有的单一功能片式元器件无论从尺寸或功能、性能、可靠性等均远远不能满足需求。SMD采用混合微电子技术,进一步向混合集成化发展,已成为必然趋势。其中应用最多的是低温共烧陶瓷(LTCC)技术、多芯片组件(MCM)技术以及球栅阵列(BGA)封装技术、芯片尺寸封装(CSP)技术。     

高密度封装技术的发展

本文简要介绍了BGA与CSP的概念、发展现状、应用情况及发展趋势等.BGA/CSP是是现代组装技术的两个新概念,它们的出现促进sMT(表面贴装技术)与SMD(表面贴装元器件)的发展和革新,并将成为高密度、高性能、多功能及高I/O数封装的最佳选择.     

高密度封装技术的发展

本文简要介绍了BGA与CSP的概念、发展现状、应用情况及发展趋势等.BGA/CSP是现代组装技术的两个新概念,它们的出现促进SMT(表面贴装技术)与SMD(表面贴装元器件)的发展和革新,并将成为高密度、高性能、多功能及高I/O数封装的最佳选择.     

高密度封装技术的发展

摘要:重点介绍了BGA与CSP高密度封装技术的发展现状及趋势。BGA与CSP是现代组装技术的两个新概念,它们的出现促进了表面贴装技术(SMT)与表面贴装元器件(SMD)的发展和革新,并将成为高密度、高性能、多功能及高I/O数封装的最佳选择。     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks     

Call for Papers—Feature Topic,Vol.12,No.7,2015

正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first     

JOURNAL OF ELECTRONICS(CHINA)

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NEXT GENERATION WIRELESS NETWORKS–ESPECIALLY THE USE OF MILLI-MICROWAVE BANDS

The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave （ram-wave） frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.