3～20GHz宽带行波低噪声放大器的设计

介绍了基于0.15μm GaAs pHEMT工艺设计的3～20GHz MMIC宽带行波低噪声放大器。在整个宽频带范围内实现了大于11.5dB的功率增益,增益平坦度1.5dB,小于4.2dB的噪声系数,以及良好的输入输出回波损耗。最大饱和输出功率达到21dBm。该4级级联行波放大器的芯片面积仅为1.5mm×1.5mm。     

5～10 GHz MMIC低噪声放大器

采用稳懋公司150 nm GaAs赝配高电子迁移率晶体管(PHEMT)工艺,设计了一款5 ～ 10 GHz单片微波集成电路(MMIC)低噪声放大器(LNA).该LNA采用三级级联结构,且每一级采用相同的偏压条件,电路的低频工作端依靠电容反馈,高频工作端依靠电阻反馈调节阻抗匹配,从而实现宽带匹配,芯片面积为2.5 mm×1 mm.测试结果表明,工作频率为5～10 GHz,漏极电压为2.3V,工作电流为70 mA时,LNA的功率增益达到35 dB,平均噪声温度为82 K,在90％工作频段内输入输出回波损耗优于-15 dB,1 dB压缩点输出功率为10.3 dBm,仿真结果与实验结果具有很好的一致性.     

1.1 dB噪声系数的单片微波集成低噪声放大器

设计与实现了一款两级赝配高电子迁移率晶体管(PHEMT)单片微波集成电路(MMIC)低噪声放大器(LNA)。考虑到实际片上无源电感的性能(低Q值),最优噪声匹配往往不能获得最好的噪声性能,相反因为输入电感的存在会增加芯片的面积。设计旨在选择合适的输入晶体管,以免除输入电感的使用,减小芯片的面积。经过优化设计,芯片尺寸为0.8 mm×0.8 mm。测试结果表明,放大器在3.4~3.6 GHz频段内实现了1.1 dB的噪声系数以及25.8 dB的小信号增益,带内回波损耗最大值为-16.5 dB。在回波损耗小于-10 dB的范围内,电路带宽拓展到2.8~4.7 GHz,此时增益最小值为20 dB,噪声最大值为1.3 dB。     

1MHz～40GHz超宽带分布式低噪声放大器设计

为满足宽带系统中低噪声放大器(LNA)宽带的要求,采用0.15μm GaAs赝配高电子迁移率晶体管(PHEMT)工艺,设计了两款1 MHz^40 GHz的超宽带LNA,分别采用均匀分布式放大器结构及渐变分布式放大器结构,电路面积分别为1.8 mm×0.85 mm和1.8 mm×0.8 mm。电磁场仿真结果表明,1 MHz^40 GHz频率范围内,均匀分布式LNA增益为15.3 dB,增益平坦度为2 dB,噪声系数小于5.1 dB;渐变分布式LNA增益为14.16 dB,增益平坦度为1.74 dB,噪声系数小于3.9 dB。渐变分布式LNA较均匀分布式LNA,显著地改善了增益平坦度、噪声性能和群延时特性。     

S波段小型化宽带低噪声放大器的设计

采用软件计算微带平面电感,描述了一款基于薄膜工艺的小型化宽带低噪声放大器的设计和性能。测试结果表明:在2.7～3.5 GHz的频段内,低噪声放大器的噪声系数小于等于0.55 dB,增益大于等于33 dB,增益平坦度小于等于±0.1 dB;在2～4 GHz的频段内,低噪声放大器的噪声系数小于等于0.65 dB,增益大于等于33 dB,增益平坦度小于等于±0.8 dB;尺寸为6.0 mm×4.2 mm。     

一种宽带CMOS低噪声放大器

基于130 nm CMOS工艺设计了一款宽带低噪声放大器(LNA),适用于Ka波段的5G应用。通过降低输入阻抗与最佳源阻抗的偏差以抑制噪声,该LNA实现了宽带的最佳噪声系数匹配。一方面,该LNA采用由LC串联组合和LC并联组合构成的宽带前端网络,在取得低噪声系数的同时,实现了宽带输入匹配;另一方面,通过体隔离技术和级间电感匹配技术提高了电路增益。同时,通过并联峰值负载技术,提高了LNA的带内增益平坦度。测试结果表明,该LNA的峰值增益为11.2 dB,-3 dB带宽为7.5 GHz(29.1～36.6 GHz)。噪声系数为5.9～6.6 dB,与仿真的最小噪声系数非常接近。输入反射系数(<-10 dB)带宽为6.7 GHz(28.3～35 GHz)。该LNA在1.2 V电源电压下功耗为9 mW,芯片面积为0.54 mm²。     

一种用于超宽带接收机的CMOS可变增益低噪声放大器

本文介绍一种符合中国超宽带应用标准的工作频率范围为4.2-4.8 GHz的CMOS可变增益低噪声放大器(LNA)。文章主要描述了LNA宽带输入匹配的设计方法和低噪声性能的实现方式,提出一种3位可编程增益控制电路实现可变增益控制。该设计采用0.13-μm RF CMOS工艺流片,带有ESD引脚的芯片总面积为0.9平方毫米。使用1.2 V直流供电,芯片共消耗18 mA电流。测试结果表明,LNA最小噪声系数为2.3 dB,S(1,1)小于-9 dB,S(2,2)小于-10 dB。最大和最小功率增益分别为28.5 dB和16 dB,共设有4档可变增益,每档幅度为4 dB。同时,输入1 dB压缩点是-10 dBm,输入三阶交调为-2 dBm。     

0.2μm GaAs PHEMT3.1~10.6GHz宽带低噪声放大器设计

采用OMMIC公司提供的0.2μm GaAs PHEMT工艺(fT=60 GHz)设计并实现了一种适用于宽带无线通信系统接收前端的低噪声放大器。在3.1~10.6 GHz的频带内测试结果如下:最高增益为13 dB;增益波动<2dB;输入回波损耗S11<-11 dB;输出回波损耗S22<-16 dB;噪声系数NF<3.9 dB。5 V电源供电,功耗为120mW。芯片面积为0.5 mm×0.9 mm。与近期公开发表的宽带低噪声放大器测试结果相比较,本电路结构具有芯片面积小、工作带宽大、噪声系数低的优点。     

X波段宽带单片低噪声放大器

从获取放大器的等噪声系数圆最大半径的角度来进行电路设计,设计了工作于X波段9～14GHz的宽带低噪声单片放大器,采用法国OMMIC公司的0.2μmGaAsPHEMT工艺(fT=60GHz)研制了芯片。在片测试结果为在9～14GHz,噪声系数<2.5dB,最小噪声系数在10.4GHz为2.0dB,功率增益在所需频段9～14GHz大于21dB,输入回波损耗<-10dB,输出回波损耗<-6dB。在11.5GHz,输出1dB压缩点功率为19dBm。     

5～13 GHz GaAs限幅低噪声放大器MMIC

基于0.15 μm GaAs pin二极管和GaAs PHEMT工艺,设计并实现了一款5～13 GHz限幅低噪声放大器(LNA)单片微波集成电路(MMIC).该MMIC中限幅器采用三级反向并联二极管结构,优化了插入损耗和耐功率性能;LNA采用两级级联设计,利用负反馈和源电感匹配,在宽带下实现平坦的增益和较小的噪声;限幅器和LNA进行一体化设计,实现了宽带耐功率和低噪声目标.测试结果表明,在5～13GHz内,该MMIC的小信号增益大于20 dB,噪声系数小于1.8 dB,耐功率大于46 dBm(2 ms脉宽,30％占空比),总功耗小于190 mW,芯片尺寸为3.3 mm×1.2 mm.限幅LNA MMIC芯片的尺寸较小,降低了组件成本,同时降低了组件装配难度,提高通道之间的一致性.     

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

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.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.