高介电(1–x)Ca_(0.7)Nd_(0.2)TiO_(3-x)Ba_(0.4)Sr_(0.6)TiO_3陶瓷微波介电特性

采用固相反应法制备了具有钙钛矿结构的(1–x)Ca_(0.7)Nd_(0.2)TiO_(3-x)Ba_(0.4)Sr_(0.6)TiO_3(0.05≤x≤0.5)陶瓷,并对其烧结行为、相组成、显微结构及微波介电性能进行了研究。结果表明:随着(Ba0.4Sr0.6)2+含量的增加,(1–x)Ca_(0.7)Nd_(0.2)TiO_(3-x)Ba_(0.4)Sr_(0.6)TiO_3(0.05≤x≤0.5)陶瓷的品质因数(Q·f)及谐振频率温度系数(τf)单调递减,而相对介电常数(εr)先升后小幅降低。当x=0.2,且烧结温度为1 450℃时,该介质陶瓷的微波介电性能为:εr=151.3,Q·f=5 900 GHz,τf=399.4×10–6/℃。与CaTiO_3(εr=160,Q·f=6 800 GHz,τf=850×10–6/℃)相比,Q·f和εr略微降低,τf有较大程度的减少,故此陶瓷体系有望替代CaTiO_3成为新一类高介电性微波陶瓷。     

添加TiO_2对0.94 ZnTiNb_2O_8-0.06 BaCu(B_2O_5)材料的物相组成及介电性能的影响

采用传统固相反应法制备了(1–x)(0.94ZnTiNb_2O_8-0.06Ba Cu(B_2O_5))-xTiO_2(0.038≤x≤0.091)微波介质陶瓷,研究了不同含量TiO_2添加对0.94ZnTiNb_2O_8-0.06BaCu(B_2O_5)(0.94ZTN-0.06BCB)陶瓷烧结特性、相结构、微观形貌以及微波介电性能的影响。结果表明:(1–x)(0.94ZTN-0.06BCB)-x TiO_2陶瓷均由ZnTiNb_2O_8和Zn_(0.17)Ti_(0.5)Nb_(0.33)O_2相组成,随着TiO_2含量的增加,陶瓷的烧结温度、εr和τf增加,ρ和Q·f降低。烧结温度为880℃时,0.926(0.94ZTN-0.06BCB)-0.074TiO_2陶瓷表现出了优良的综合性能:εr=40.25,Q·f=32 000 GHz(5.89 GHz),τf=–3.86×10–6℃–1。且在此温度下介质材料与Ag电极兼容性良好,表明该材料是制备LTCC器件的备选材料。     

低温烧结(1–x)Ba_3(VO_4)_(2-x)Li_2WO_4微波介质陶瓷的研究

为了获得低温烧结的陶瓷材料,用固相反应制备了(1–x)Ba3(VO4)2-x Li2WO4(0.05≤x≤0.20)微波介质陶瓷。实验结果表明:随着添加剂Li2WO4的增加,复合陶瓷的相对体密度、相对介电常数εr和品质因数Q·f都呈现出先增加随后又降低的趋势,而谐振频率温度系数τf呈线性降低。添加了摩尔分数0.15Li2WO4的微波介质陶瓷在850℃烧结2 h达到约96.8%的致密度,并获得最佳的微波介电性能:εr=13.7,Q·f=97000 GHz,τf=1.8×10–6/℃。     

温度稳定型Li_2(Zn_(1–x)Co_x)_2Mo_3O_(12)陶瓷的微波介电性能研究

采用固相反应法制备了Li_2(Zn_(1–x)Co_x)_2Mo_3O_(12)陶瓷,研究了Co~(2+)取代对其相结构和微波介电性能的影响,并通过添加Ti O_2调节了该陶瓷的τ_f值。结果表明:不同Co~(2+)取代的Li_2(Zn_(1–x)Co_x)_2Mo_3O_(12)陶瓷均显示出单相钒铁铜矿结构。随着Co~(2+)取代量的增加,陶瓷的致密化温度显著降低,相对密度和Q·f值均呈现先增大后减小的趋势。当x=0.1时,陶瓷具有相对较好的微波介电性能:ε_r=10.85,Q·f=65 031 GHz,τ_f=–73×10~(–6)/℃。添加Ti O_2能够有效调节Li_2Zn_2Mo_3O_(12)陶瓷的τ_f值向正值方向移动,0.4Li_2(Zn_(0.9)Co_(0.1))_2Mo_3O_(12)-0.6Ti O_2陶瓷的介电性能较佳:ε_r=15.80,Q·f=22 991 GHz,τ_f=–4.5×10~(–6)/℃。     

CNT对BST陶瓷微波介电性能的影响

采用XRD及SEM研究(Ca0.61Nd0.26)TiO3对微波介质陶瓷Ba4Sm9.33Ti18O54的结构和微波介电性能的影响。获得了一些性能较好的微波介质陶瓷(1–x)Ba4Sm9.33Ti18O54-x(Ca0.61Nd0.26)TiO3,其微波介电性能如下:εr=75,Q·f为8985GHz,τf为–8.2×10–6℃–1(x?=0);εr为75,Q·f为9552GHz,τf为–14.4×10–6℃–1(x?=0.2)。     

非化学计量比Li_(2+x)ZnTi_3O_(8+0.5x)微波介质陶瓷的性质研究

采用传统固相反应法制备Li2+xZnTi3O8+0.5x微波介质陶瓷,研究了A位Li的非化学计量比对Li2+xZnTi3O8+0.5x陶瓷的烧结特性、相结构及微波介电性能的影响。结果表明:随着Li2+xZnTi3O8+0.5x(x=–0.2～+0.2)陶瓷中Li含量的逐渐增加,TiO2相逐渐消失,陶瓷的致密度逐渐升高,介电常数逐渐降低,Q.f值先上升再下降,谐振频率温度系数逐渐降低,然后保持不变。当x=–0.05时,Li1.95ZnTi3O7.975陶瓷取得最佳的综合微波介电性能:εr=26.41,Q.f=65 200 GHz,τf=–4.16×10–6/℃。     

CaTiO3-（La,Nd）AlO3微波介质陶瓷的研究与应用

为了降低材料成本,研究了(1–x)CaTiO3–x(La1–yNdy)AlO3微波介质陶瓷的性能与组成之间的关系。采用固相法制备粉料,在1 400℃下烧结,用XRD和SEM分析陶瓷的晶相组成和显微结构,采用闭腔法测量其微波介电性能。研究结果表明该陶瓷形成单一晶相固溶体,当x=0.35,y=0.286时,εr=43,Q.f=30 000 GHz,τf=5×10–6/℃。用该陶瓷制作了基站用环形介质谐振器,其性能如下:f0=2.122 0 GHz,Q=12 436,fs/f0=1.220,与仿真结果非常吻合。     

钙钛矿锰氧化物Ca_(0.5)Nd_(0.5)(Mn_(0.7)Fe_(0.3))O_3掺杂对Ca_(0.61)Nd_(0.26)TiO_3微波介电性能的影响

研究了传统固相反应法制备所得xCa_(0.5)Nd_(0.5)(Mn_(0.7)Fe_(0.3))O_3-(1–x)Ca_(0.61)Nd_(0.26)TiO_3(0.1≤x≤0.25,CNMFT_x)多晶陶瓷相组成、显微结构、烧结性能与微波介电性能之间的影响关系。X射线衍射研究表明,在研究组分范围内CNMFT_x样品均为单一正交钙钛矿结构;当烧结条件为1 400℃/4 h,x=0.1~0.2时,Fe~(3+)/Mn~(3+,4+)替代Ca_(0.61)Nd_(0.26)TiO_3中Ti~(4+)后,相对介电常数(εr为88.5~77.5)、品质因子(Q·f为7 010~9 370 GHz)和谐振频率温度系数(τf为207.4×10~(–6)/℃~149.1×10~(–6)/℃)逐渐降低,而当x=0.25时,εr(73.4)与τf值(119.6×10~(–6)/℃)仍按规律降低,虽然此时样品晶粒尺寸更为均匀,但Q·f值(5 100 GHz)降幅增加。因此,对于ABO3型钙钛矿结构的微波介质陶瓷,当具有铁磁效应离子的添加量较小时,微波介电性能的变化符合预期规律;但当置换量达到一定比例时,铁磁性增加,导电性增强,巨磁电阻效应减小,致使微波陶瓷介电损耗增加。     

CaWO_4-Mg_2SiO_4陶瓷的微波介电性能与应用

为了使微波介电陶瓷在厘米波段获得应用,采用固相法制备了低εr、高Q·f值的(1–x)CaWO4-xMg2SiO4(x=0～1.0)介电陶瓷,并添加质量分数为5%的TiO2调节其τf。研究了其晶相结构和微波介电性能。结果表明,x≤0.2时,Mg2SiO4和CaWO4形成不完全固溶体;x=0.2时,在1300℃烧结2h所制得的陶瓷具有优良的微波介电性能:εr=9.58,Q·f=56400GHz,τf=–8.2×10–6/℃,并采用该材料制作了f0=5.4909GHz,插入损耗小于1.1dB,外形尺寸为5.0mm×2.5mm×4.0mm的两级片式介质带通滤波器。     

中温制备钛酸钕钙-钛酸钕锂系高介微波陶瓷

将温度系数相反的钛酸钕钙(CNT)和钛酸钕锂(LNT)进行复合,中温下(1200℃)烧结获得了εr>100的CNT-LNT微波介质陶瓷。该陶瓷为斜方结构的CaTiO3基固溶体单相。介电常数随x增加先增加后减小,在x=0.5处最大。Q.f值和谐振频率温度系数随LNT含量增加而线性下降。中温下制备了性能良好的CNT-LNT系微波介质陶瓷,如x=0.6时微波性能为:εr=123.9,Q.f=1500GHz,τf=12.0×10–6℃–1。     

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。     

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.     

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.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

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.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.