射频微机械CPW开关的研究

本文采用聚酰亚胺牺牲层技术和二氧化硅介质隔离技术,成功地在绝缘多晶硅衬底上研制出一种射频微机械CPW开关.初步测试结果如下:开态电容为0.21pF,关态电容为6.1pF,致动电压为22V,关态下的隔离度为35dB,开态下插入损耗为3dB.该工艺完全与硅基IC工艺兼容,这为射频微机械CPW开关与IC实现单片集成化,降低体积提高可靠性打下了基础.     

双膜桥微波MEMS开关

介绍了一种双膜桥微波MEMS开关，给出了开关的设计与优化方法，建立了开关的仿真模型，使用硅表面微机械工艺制造了双膜桥开关样品，其主要结构为硅衬底上制作CPW金属传输线电极和介质层，然后制作具有微电感结构的金属膜桥，提高了开关隔离度。利用HFSS软件仿真的结果表明，该开关在微波低频段(3～6GHz)有着很好的隔离性能。研制的开关样品在片测试的电性能指标为：插损小于0．3dB，隔离度大于40dB，驱动电压小于24V。     

双膜桥微波MEMS开关

介绍了一种双膜桥微波MEMS开关,给出了开关的设计与优化方法,建立了开关的仿真模型,使用硅表面微机械工艺制造了双膜桥开关样品,其主要结构为硅衬底上制作CPW金属传输线电极和介质层,然后制作具有微电感结构的金属膜桥,提高了开关隔离度.利用HFSS软件仿真的结果表明,该开关在微波低频段(3～6GHz)有着很好的隔离性能.研制的开关样品在片测试的电性能指标为:插损小于0.3dB,隔离度大于40dB,驱动电压小于24V.     

双膜桥微波MEMS开关

介绍了一种双膜桥微波MEMS开关 ,给出了开关的设计与优化方法 ,建立了开关的仿真模型 ,使用硅表面微机械工艺制造了双膜桥开关样品 ,其主要结构为硅衬底上制作CPW金属传输线电极和介质层 ,然后制作具有微电感结构的金属膜桥 ,提高了开关隔离度。利用HFSS软件仿真的结果表明 ,该开关在微波低频段 (3～ 6GHz)有着很好的隔离性能。研制的开关样品在片测试的电性能指标为 :插损小于 0 .3dB ,隔离度大于 4 0dB ,驱动电压小于 2 4V。     

微机械微波/射频开关的制备和功能测量研究

讨论了微机械微波/射频开关的原理、制备工艺和功能测试.微机械接触式微波/射频开关的基本结构是微波共平面波导,在制备工艺中首先考虑的是工艺兼容性,为此选择以PECVD生长的氮化硅为悬臂梁,聚酰亚胺为牺牲层.功能测试表明,该工艺制备的微机械开关的执行电压只有25V,优于同类微机械开关的指标,同时它具有良好的响应特性.     

基于砷化镓衬底的RF MEMS膜开关

射频微机械开关由于其优越的高频特性在微波和毫米波电路中表现出巨大的应用前景。但是目前的微机械开关都是制作在硅基衬底上的，难于与后面的高频砷化镓处理电路相集成。本文介绍了基于砷化镓衬底的RFMEMS膜开关，着重介绍了开关的工作原理、制作过程和测试结果。     

基于砷化镓衬底的RF MEMS膜开关

在低损耗的微波和毫米波电路中 ,静电驱动的射频微机械 (MEMS)开关表现出巨大的应用前景。和传统的半导体开关相比 ,由于在结构上消除了金属 -半导体结和 PN结 ,MEMS开关具有极其优越的高频特性 ,例如 MEMS开关具有极低的插入损耗和较高的隔离度。简单的来说 ,射频微机械开关是由静电驱动的金属梁和射频信号线构成。自从 1 979年 Petersen首次研制出金属包覆的静电悬臂梁开关以来 ,多种结构形式的 MEMS开关被用于控制微波信号 ,例如悬臂梁结构、旋转传输线结构和膜结构等。到目前为止 ,研究的射频微机械开关主要有两种结构形式 :金…     

基于砷化镓衬底的RF MEMS膜开关

射频微机械开关由于其优越的高频特性在微波和毫米波电路中表现出巨大的应用前景。但是目前的微机械开关都是制作在硅基衬底上的 ,难于与后面的高频砷化镓处理电路相集成。本文介绍了基于砷化镓衬底的RFMEMS膜开关 ,着重介绍了开关的工作原理、制作过程和测试结果     

一种用于隔离放大器的微机械开关

介绍了一种新型的隔离放大电路,采用微机械开关实现“飞电容”结构。这种隔离放大电路具有许多优点:电路结构简单、尺寸小、成本低、隔离电压高、电磁兼容性能优良,很容易组成多通道隔离电路等;在30V驱动电压下测试,微机械开关的延时小于50μs,隔离电压大于110V。对设计、制造出的微机械开关隔离放大器进行了测试,证明该电路的精度优于2%。     

基于砷化镓衬底的RF MEMS膜开关

射频微机械开关由于其优越的高频特性在微波和毫米波电路中表现出巨大的应用前景.但是目前的微机械开关都是制作在硅基衬底上的,难于与后面的高频砷化镓处理电路相集成.本文介绍了基于砷化镓衬底的RF MEMS膜开关,着重介绍了开关的工作原理、制作过程和测试结果.     

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.     

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.     

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.     

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.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

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.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.