毫米波单片平衡放大器

研制了一款毫米波(26～40 GHz)平衡式单片放大器芯片。放大器基于0. 15μm GaAs pHEMT工艺,实现了毫米波全频段(26～40 GHz)增益放大。采用Lange桥平衡结构,使放大器较于单边放大器有更好的输入输出驻波比,更大的1 dB增益压缩输出功率。设计时结合pHEM T晶体管小信号和大信号模型,采用自偏和RLC并联负反馈结构,在减小芯片面积的同时提高了电路的稳定性。放大器芯片尺寸仅1. 6 mm×1. 6 mm,在工作频率26～40 GHz内,测试结果表明:输入、输出驻波比小于1. 5,增益在11 dB附近,平坦度在±0. 5 dB,1 dB增益压缩输出功率大于11 dBm。测试结果验证了设计的正确性。     

Ka波段单片低噪声放大器

利用0.25 μm GaAs PHEMT工艺设计并制作了一种Ka波段低噪声放大器芯片.提出了适用于低噪声放大器的PHEMT器件特征.电路采用四级级联结构.利用微带电路实现输入、输出和级间匹配.通过对电路增益、噪声系数和驻波比等指标进行多目标优化,确定了器件参数.该放大器测试结果为:26.5～36 GHz频段内增益大于20 dB;多数测试点噪声系数小于3 dB,其中34 GHz频点噪声仅为1.94 dB;芯片面积2.88 mm×1 mm.     

2～4GHz MMIC低噪声放大器

采用中国电子科技集团公司第十三研究所的GaAs PHEMT低噪声工艺,设计了一款2~4 GHz微波单片集成电路低噪声放大器(MMIC LNA)。该低噪声放大器采用两级级联的电路结构,第一级折中考虑了低噪声放大器的最佳噪声和最大增益,采用源极串联负反馈和输入匹配电路,实现噪声匹配和输入匹配。第二级采用串联、并联负反馈,提高电路的增益平坦度和稳定性。每一级采用自偏电路设计,实现单电源供电。MMIC芯片测试结果为:工作频率为2~4 GHz,噪声系数小于1.0 dB,增益大于27.5 dB,1 dB压缩点输出功率大于18 dBm,输入、输出回波损耗小于-10 dB,芯片面积为2.2 mm×1.2 mm。     

4～20GHz超宽带低噪声放大器单片电路

采用分布式放大器设计原理,基于GaAs PHEMT低噪声工艺技术,研制了一款超宽带低噪声放大器单片电路。该款放大器选用分布式拓扑结构,由五级电路构成,为了进一步提高分布式放大器的增益,在每一级又采用了两个场效应晶体管(FET)串联结构。放大器采用了自偏压单电源供电,因为每级有两个FET串联,自偏压电路更为复杂,通过多个电阻分压的方式确定了每个FET的工作点。测试结果表明,该放大器在频率4～20 GHz内,增益大于14 dB,噪声系数小于3.0 dB,增益平坦度小于±1.0 dB,输入驻波比小于1.5∶1,输出驻波比小于1.8∶1,1 dB压缩点输出功率大于10 dBm。放大器的工作电压为8 V,电流约为50 mA,芯片面积为2.0 mm×2.0 mm。     

采用电流复用技术的8mm频段低噪声放大器

利用电流复用技术设计8mm频段低噪声放大器芯片,采用0.15μm GaAs PHEMT工艺,芯片尺寸为1.73mm×0.75mm×0.1mm。测试结果显示:在32～38GHz频带内,放大器增益大于21dB,噪声系数小于1.85dB,输入、输出电压驻波比小于2.5,P1 dB大于7dBm,功耗5V,28mA,采用电流复用技术比传统设计的功耗降低将近40%。     

具有正斜率增益的GaAs MMIC宽带放大器芯片设计

介绍了一种宽带放大器芯片,该放大器的工作频率覆盖了2～12 GHz,采用砷化镓(GaAs)赝配高电子迁移率晶体管(PHEMT)单片电路工艺实现。在一个宽带负反馈放大器的前面集成了一个幅度均衡器,使放大器的增益在整个带内具有7 dB的正斜率,频率低端(2 GHz)增益为3 dB,高端(12 GHz)为10 dB,输入输出电压驻波比为1.6∶1,饱和输出功率为20 dBm,芯片尺寸为2.0 mm×1.5 mm×0.1 mm。详细描述了电路的设计流程,并对最终的测试结果进行了分析。该芯片具有频带宽、体积小、使用方便的特点,可作为增益块补偿微波系统中随着频率升高而产生的增益损失。     

X波段PHEMT功率单片放大器

报道了X波段8W AlGaAs/InGaAs/GaAs PHEMT MMIC功率单片放大器的设计和研制.放大器采用两级拓扑结构,输入输出为50Ω阻抗匹配,芯片面积为4.5mm×3mm.测试结果显示,在7.5V和1.5A的DC偏置下,输出功率在8W以上,功率附加效率为30%,功率增益为15dB.     

X波段PHEMT功率单片放大器

报道了X波段8W AlGaAs/InGaAs/GaAs PHEMT MMIC功率单片放大器的设计和研制.放大器采用两级拓扑结构,输入输出为50Ω阻抗匹配,芯片面积为4.5mm×3mm.测试结果显示,在7.5V和1.5A的DC偏置下,输出功率在8W以上,功率附加效率为30%,功率增益为15dB.     

采用电流复用拓扑的宽带收发一体多功能电路

基于标准的GaAs赝配高电子迁移率晶体管(PHEMT)单片微波集成电路(MMIC)工艺设计并制备了一款宽带收发一体多功能电路芯片.该多功能芯片包含了功率放大器、低噪声放大器和收发开关.放大器采用电流复用拓扑结构实现了低功耗的目标.收发开关采用浮地结构避免了使用负电源.芯片在14～ 24 GHz工作频率的实测结果显示:接收支路噪声系数小于3.0dB,增益大于18 dB,输入及输出电压驻波比(VSWR)均小于2.0,1 dB压缩点输出功率大于0 dBm,直流功耗为60 mW;发射支路增益大于21 dB,输入输出VSWR均小于1.8,1dB压缩点输出功率大于10 dBm,直流功耗为180 mW.芯片尺寸为2 600 μm×1 800 μm.该多功能收发电路的在片测试结果和仿真结果一致,性能达到了设计要求.     

基于GaAs PHEMT的6~10GHz多功能芯片

介绍了一种基于GaAs PHEMT工艺的多功能芯片(MFC)设计。该芯片主要用于双向放大,具有低噪声性能和中等功率能力。综合考虑噪声、功率、效率和有源器件的正常工艺波动,选取合适的器件及其工作点、电路拓扑结构,使电路性能达到最优。采用大信号模型、噪声模型和开关模型联合仿真完成该芯片设计,并对版图进行电磁场仿真。测试结果表明,在6~10GHz频带内:小信号增益大于18.5 dB,增益平坦度小于±0.2 dB,输入/输出电压驻波比小于1.4:1,噪声系数小于2.2 dB,1 dB压缩点输出功率大于14 dBm。芯片尺寸为2.4 mm×2.6 mm。     

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.