双模方形谐振腔增益均衡器的设计与实现

针对均衡器小型化、高Q值的应用需求,提出并设计了一个工作在Ku波段的双模方形基片集成波导谐振腔均衡器.设计了两个正交的耦合缝隙,在谐振腔中激励起简并模TE₂₀₁和TE₁₀₂;使用金属柱微扰其中一个模式,实现独立调节该模式的谐振频率,并且频率调节自由度高;研究了薄膜电阻的加载位置,实现独立调节两个模式的衰减量和Q值;分析了双模谐振腔级联后谐振频率偏移量及可调性,给出了双模谐振腔均衡器的分析和设计方法.相比于传统单模谐振腔均衡器,该结构均衡器保持了原有的工作性能,并减少了一半数量的谐振腔,使得结构更加紧凑.测试结果与仿真结果吻合,最大误差0.4dB.     

电阻加载的螺旋形谐振器在微带均衡器中的应用

本文给出了一种薄膜电阻加载的矩形螺旋形谐振器,并利用其设计了一种甚小尺寸的微带均衡器子结构电路,对薄膜电阻的加载位置也进行了研究.通过在螺旋形谐振器中引入电阻加载,使得该电路能够进行品质因数调节.分析表明这种电阻加载的螺旋形谐振器不仅能够进行中心频率调节、曲线衰减幅度调节,而且能够对谐振回路的品质因数进行调节,适合在微带均衡器中应用,为微带均衡器的设计提供了一种新的设计途径.     

电阻加载的螺旋型谐振器在微带均衡器中的应用

提出了一种薄膜电阻加载的矩形螺旋型谐振器,并利用其设计了一种甚小尺寸的微带均衡器子结构电路,对薄膜电阻的加载位置也进行了研究.通过在螺旋型谐振器中引入电阻加载,使得该电路能够进行品质因数调节.利用高频结构仿真软件分析表明这种电阻加载的螺旋型谐振器不仅能够进行中心频率调节、曲线衰减幅度调节,而且能够对谐振回路的品质因数进行调节,适合在微带均衡器中应用,为微带均衡器的设计提供了一种新的设计途径.     

电阻加载在宽带均衡器中的应用

给出了1种宽带的功率均衡器的快速设计方法。分析了均衡网络中加载电阻后谐振单元的谐振和耦合特性,并讨论了加载电阻对谐振单元品质因数的影响。对谐振单元的尺寸和电阻进行设定和调整,并使用仿真软件对级联网络进行优化,可以在短时间内设计出满足目标的均衡器。基于本方法,设计了2种频段的宽带功率均衡器。     

Ka波段微带线增益均衡器设计

本文设计出一个匹配良好的Ka波段微带线增益均衡器,驻波比在带内小于1.5。选择薄膜电阻加载的枝节谐振单元作为构成陷波器响应的基本结构。通过大量的仿真和分析,研究了谐振单元中枝节的位置、宽度和长度及薄膜电阻的长度和阻值等参量对衰减曲线的影响。利用三个加载了不同阻值的枝节谐振单元得到了一个Ka波段微带线增益均衡器,给出了结构图及衰减曲线S21和驻波比ρ的曲线。结果表明这种加载薄膜电阻的谐振单元适合Ka波段微带线增益均衡器的设计。     

电阻加载环形谐振器在微带均衡器中的应用

文中提出了一种薄膜电阻加载的微带环形谐振器,并用其设计了一种新型均衡器子机构。研究表明:通过电阻加载的环形谐振器不仅具有中心频率和衰减幅度调节功能,而且能够对电路的品质因数进行调节,为均衡器的设计提供了极大的方便。最后给出了利用这种形环谐振器设计的均衡器的典型曲线。     

薄膜电阻对微带均衡器的影响研究

为了使微带均衡器满足衰减特性与给定的误差曲线逐点拟和的要求,就必须使其频率可调、衰减可调、品质因数可调。因此,本文通过大量仿真和实验,研究了加载了薄膜电阻的微带谐振器及其在微带均衡器中的应用,研究分析了薄膜电阻对微带均衡器传输特性及驻波特性的影响。研究结果表明将薄膜电阻加载到微带谐振器上构造微带均衡器,可以通过改变谐振器的尺寸使其频率可调,通过改变电阻阻值及位置使其衰减可调、品质因数可调。大量HFSS仿真及实验证明这种方式很适合微带均衡器的设计制造。本文利用这种结构设计制作出了一个宽带微带均衡器,得到了很好的实验结果。     

12 GHz枝节匹配宽带微带均衡器

给出了一种匹配良好的宽带微带均衡器的设计。它由在枝节上加载了薄膜电阻的微带枝节谐振器构造而成。通过大量的试验和仿真研究了电阻值对谐振器的影响。当加载薄膜电阻在枝节谐振器上时，可以得到可调的品质因数。利用HFSS分析可以看到电阻加载的枝节谐振器不仅频率可调，而且衰减可调、品质因数可调。文中利用四个加载了不同阻值的枝节谐振器得到了一个12GHz带宽的微带均衡器，给出了结构图和特性曲线。结果表明这种加载电阻的谐振器结构很适合宽带微带均衡器设计。     

X波段宽带低差损功率均衡器的设计与实现

功率均衡器是改善微波系统幅度响应平坦度的一种有效的解决办法。文中研究了电阻加载谐振网络及其在宽带功率均衡器中的应用。利用ADS仿真软件对电阻加载宽带功率均衡器进行联合电磁仿真设计与优化,实现了X波段宽带低差损功率均衡器。均衡器在整个频带内均衡5 dB,输入输出驻波比均小于1.5∶1,最终测试结果与初始设计相吻合,满足了工程需要。结果表明,电阻加载均衡器适用于宽带功率均衡器的研制。     

宽带功率均衡器的匹配电路设计

将宽带匹配理论引入功率均衡器的分析,并基于分析设计了一个6～18GHz均衡器的匹配网络。电阻加载后的谐振枝节特性对均衡器很重要,也正由于该谐振枝节的引入,将引入失匹配,则要对谐振枝和输入输出端口进行匹配。基于对谐振枝节特性、枝节间匹配网络及匹配约束理论的分析,成功设计了一个频段为6～18GHz的微波均衡器。     

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.     

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.     

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.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.