基于绝缘体上硅材料的25通道200 GHz的阵列波导光栅（英文）

报道了基于绝缘体上硅材料的25通道、信道间隔200 GHz的阵列波导光栅,分别优化了输入波导/输出波导/阵列波导间的最小间距(Δx_i/Δx_o/d),及其自由传播区和阵列波导之间边界结构(W_2/L_2/L_3).实验结果表明,该阵列波导光栅的插入损耗为5～7 dB,串扰为13～15 dB,该阵列波导光栅的性能得到有效提升.同时也提出了减小插损与串扰的进一步优化方案.     

一种降低列阵波导光栅相邻信道串扰的方法

阵列波导光栅 (AWG)作为波长滤波器在光通信领域具有很大的应用前景。串扰是影响阵列波导光栅应用的重要因素之一。为了降低阵列波导光栅相邻信道的串扰 ,本文提出并研究了一种降低阵列波导光栅的新方法。该方法利用阵列波导光栅的衍射特点性 ,通过调节阵列波导光栅的自由光谱范围 (FSR)、罗兰圆焦距和阵列波导数目 ,使得各信道信号的输出极小值处于其它信道输出波导中心 ,无次极大处于其它波导中 ,从而降低了阵列波导光栅的串扰 ,特别是相邻信道之间的串扰。通过光束传播方法 (BPM)的模拟了具有不同FSR的 1× 16阵列波导光栅 ,结果显示 ,该方法能将相邻信道之间的串扰降低约 5 .7dB。     

用于FBG解调的AWG芯片的设计、仿真与制备

设计、仿真并制备了一种用于光纤布拉格光栅(FBG)解调的阵列波导光栅(AWG)芯片。该芯片基于SOI衬底进行制备,并在AWG的输入/输出波导、阵列波导与平板波导之间采用双刻蚀结构进行优化。经仿真,该AWG的插入损耗为1.5dB,串扰小于 -20dB,3dB带宽为1.5nm。优化后的AWG芯片采用深紫外光刻技术、电感耦合等离子体等技术制备。经测试,该AWG的插入损耗为3dB,串扰小于 -20dB,3dB带宽为2.3nm。搭建了基于该AWG的解调系统,解调实验结果表明,该系统在0.8nm范围内的解调精度可达11.26pm,波长分辨率为6pm。     

16×0.8nm硅基二氧化硅AWG性能优化

对设计的折射率差为0.75%的16×0.8 nm硅基二氧化硅阵列波导光栅(AWG),围绕插损和串扰问题,采用广角有限差分束传播方法(FD-BPM)进行了数值模拟和优化.通过优化在输入波导、阵列波导的喇叭口,得到了插损为1.5 dB、串扰为-48 dB的AWG,优化后的指标已达到商用要求.     

Optimization of 16×0.8 nm Si-based SiO_2 Arrayed Waveguide Grating

对设计的折射率差为0.75%的16×0.8nm硅基二氧化硅阵列波导光栅(AWG),围绕插损和串扰问题,采用广角有限差分束传播方法(FD BPM)进行了数值模拟和优化。通过优化在输入波导、阵列波导的喇叭口,得到了插损为1.5dB、串扰为-48dB的AWG,优化后的指标已达到商用要求。     

基于SOI的16通道200GHz阵列波导光栅

设计并制作了基于绝缘体上硅(SOI)材料的1×16阵列波导光栅(AWG).该AWG器件的中心波长为1 550 nm,信道间隔为200 GHz,采用了脊型波导结构.首先确定了波导的结构尺寸以保证单模传输,并利用束传播法(BPM)模拟了波导间隔、弯曲半径和锥形波导长度等参数对器件性能的影响,对器件结构进行了优化,同时也利用BPM方法模拟了器件的传输谱.模拟结果显示:器件的最小信道损耗为4.64 dB,串扰小于-30 dB.根据优化的器件结构,通过光刻等半导体工艺制作了AWG,经测试得到AWG器件的损耗为4.52～8.1 dB,串扰为17～20 dB,能够实现良好的波分复用/解复用功能.     

顶部平坦化32通道AWG的设计与研制

根据优化输入端多模干涉器(MMI)结构设计,研制出32通道50 GHz通道间隔、顶部平坦化的阵列波导光栅(AWG)器件。该器件的采用6μm×6μm折射率差为0.75%的Si基SiO2埋型波导结构,阵列波导数为130,罗兰圆半径为9 419.72μm,相邻阵列波导长度差为128.42μm。测试结果表明:AWG器件插入损耗(IS)为-5~-8.5 dB,串扰>-25 dB,3 dB带宽>0.25 nm。     

箱型光谱响应聚合物阵列波导光栅的研制

通过减少奇数阵列波导的芯宽度,同时增加偶数阵列波导的芯宽度的技术,构造了箱型光谱-选用氟化聚芳醚FPE聚合物材料,设计并制备了17×17信道箱型光谱响应阵列波导光栅(AWG)波分复用器.测试结果表明,器件的中心波长为1550.87nm,波长间隔为0.8nm,3dB带宽约为0.476nm,串扰低于-21dB,插入损耗为13～15dB.     

基于绝缘层上硅平坦化阵列波导光栅的单纤三向器

设计了基于绝缘层上硅(SOI)平坦化阵列波导光栅单纤三向器.三向器三个波长(1310,1490和1550nm)工作在阵列波导光栅的三个不同的衍射级数,并在阵列波导光栅的输入波导末端引入多模干涉器(MMI),实现了平坦响应的三波长波分复用.模拟结果表明基于这一设计的三向器3dB带宽为6nm,串扰小于-40dB,插损为5dB.制备的三向器经测试输出光场清晰,实现了三向器的功能.     

基于绝缘层上硅平坦化阵列波导光栅的单纤三向器

设计了基于绝缘层上硅(SOI)平坦化阵列波导光栅单纤三向器.三向器三个波长(1310,1490和1550nm)工作在阵列波导光栅的三个不同的衍射级数,并在阵列波导光栅的输入波导末端引入多模干涉器(MMI),实现了平坦响应的三波长波分复用.模拟结果表明基于这一设计的三向器3dB带宽为6nm,串扰小于-40dB,插损为5dB.制备的三向器经测试输出光场清晰,实现了三向器的功能.     

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.