电气互联技术的现状及发展趋势

简要介绍了国外电气互联技术的现状，从电路可制造性设计、堆叠装配、FPC组装设计与工艺、PCB可制造性分析及虚拟设计技术、微波电路互联结构及绿色清洗技术等7个方面分析了电气互联先进制造技术的发展方向。     

微波电路组装工艺研究

微波电路与低频电路的不同主要在于接地,互连与微带线的制造。微波制造技术是微波电路设计的一个重要组成部分。对接地的一些关键技术一焊接裂纹、应力、变形、钎连学等作了研究。同时研究了芯片与微带线间距的互连、微带线制作、材料的可焊性及焊接过程等制造技术。     

高性能低成本微波组件制造技术

高性能、低成本的微波组件制造技术对复杂昂贵的电子系统的普及应用具有重要意义。目前,微波组件多采用薄膜或微波介质片工艺制造。其调试造手工操作来完成,制造成本较高,生产一致性差。先进的铜厚膜工艺具有微性能好、便于大量生产等特点,是一 高性能、低成本的电路基板制造技术。激光技术与自动测试技术自动控制技术相结合可实现对微波组件的高精度动态闭环自动化测试修调。采用这些先进技术,能提高生产效率。降低微波组件的     

用于制造微波多芯片组件的LTCC技术

低温共烧陶瓷(LTCC)是实现微波多芯片组件(MMCM)的一种理想的组装技术,具有高集成密度、多种电路功能和高可靠性等技术优势.介绍了国内外应用于微波组件的LTCC技术发展现状,概述了LTCC的制造工艺流程,分析了其关键工艺难点,对LTCC基板电路的设计进行了详细阐述,并讨论了埋层电阻的设计和微带线和带状线间的垂直微波互联的方式.利用LTCC技术研制的微波多芯片组件,在现代雷达和通讯领域具有广泛的应用前景.     

微波单片陶瓷电路技术研究

微波单片陶瓷电路(MMCC)是一项新兴的薄膜集成技术,是将构成微波电路的要素尽可能采用薄膜电路的实现方式集成于陶瓷基片上,并采用微细实心金属孔及空气桥、介质跨接等工艺实现接地、跨接和互联,可大大提高集成度,改善微波产品的性能.对该项技术进行了简要的介绍,并对主要的工艺技术如微小实心孔及金属化、集成电容技术、介质桥技术进行了重点阐述,同时应用MMCC技术设计和制作了微波鉴相电路,达到了预期效果.     

三维微波多芯片组件垂直微波互联技术

三维微波多芯片组件是新一代固态有源相控阵共形天线和智能蒙皮的核心部件。文章详细介绍了实现三维微波多芯片组件最关键的小型化、低插入损耗和高可靠的垂直微波互联技术,对采用毛纽扣结构的无焊接垂直微波互联和采用环氧树脂包封的垂直微波互联、微波传输结构进行了仿真和优化,研发出相应的制作工艺,实现了三维微波多芯片组件微小型化、大工作带宽、低插入损耗和高可靠垂直微波互联。     

RF/微波无线系统中的MEMS技术

着重论述了RF/微波MEMS元件及其制造技术、封装要求和设计,并在此基础上阐述RF/微波MEMS元件的应用电路和系统。     

微波印制电路快速制造技术

本文介绍了一种微波印制电路板快速制造方法及其基本原理，并对其在军用微波混合电路中应用的可行性进行了探讨及分析，结果表明这种技术能够满足L波段或S波段等常用微波领域的混合电路的快速研制及试生产的需要。     

相控阵用收发(T/R)组件

本文简要评逆相控阵用收发(T/R)组件的特点及发展概况,介绍了几种收发组件的电路,即混合微波集成电路(HMIC)、微型混合微波集成电路(MHMIC)以及单片微波集成电路(MMIC),并讨论了收发组件的制造工艺、电路组成、封装测试和成品价格。     

微波毫米波多芯片模块三维互联与封装技术

微波毫米波固态有源相控阵天线在通信、雷达和导航等电子装备中得到广泛应用,三维互联与封装技术是研制小型化、高集成和高可靠有源相控阵天线的微波毫米波多芯片模块(MMCM)的关键技术。通过开展三维多层多芯片热布局优化设计,使MMCM 温度分布均匀,保证三维MMCM 可靠工作。通过研发含有双面高精度腔体的低温共烧陶瓷(LTCC)多层电路基板,并采用球栅阵列(Ball Grid Array, BGA)和毛纽扣微波毫米波垂直互联工艺、激光密封焊接工艺,研制出小型化、高性能和高可靠性的三维微波毫米波多芯片模块,满足新一代微波毫米波相控阵天线技术要求。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

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.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.