一种基于飞秒激光白内障手术的碎核轨迹设计

针对在飞秒激光辅助晶状体碎核中,需要根据白内障患者的晶状体浑浊等级选择不同的扫描方案,且其每一层的扫描轨迹不连续的问题,提出了一种参数化的螺旋形激光扫描碎核轨迹。对螺旋形扫描轨迹进行了整体参数化定义,解出了扫描轨迹的数学模型,并求解了轨迹中关键数据点的坐标值。最后对扫描轨迹数学模型建立了仿真,其仿真结果验证了所求解扫描轨迹数学模型的正确性。此种碎核方案的每一层轨迹连续,可通过改变相应参数实现不同的切割效果,为飞秒激光辅助白内障手术提供了一种新型的碎核方案,具有一定的实用价值。     

激光光路跟踪型原子力显微镜研究

提出和发展了一种激光光路跟踪型原子力显微镜(AFM)技术及系统。研制了新型AFM探头,设 计了与XY扫描器联动的跟踪透镜及扫描跟踪光路,实现激光束对微探针(微悬 臂)的XY扫描的实时跟踪;研 究设计了独特的反馈跟踪光路,既可实现微悬臂偏转量的精确检测,又可巧妙地消除因微探 针的Z向反馈运动 造成的干扰噪声。利用研发的AFM系统对多孔氧化铝纳米孔等具有不同横向与 纵向结构尺寸的微纳米样品进行了扫 描成像,得到了理想的实验结果,表明研发的系统具有优良的XY扫描跟踪特性 和Z向反馈跟踪性能。本文研发的 AFM系统原理新颖、方法巧妙、扫描成像性能好和分辨率高,克服了常规样品 扫描型AFM的局限性,能够以 微探针扫描的方式实现不同大小、不同重量的样品的AFM扫描成像,可望在微纳米技术领 域获得广泛应用。     

高精度轴对称非球面反射镜轮廓测量方法（特邀）

为实现轴对称非球面反射镜轮廓的高精度、可溯源测量,建立了非球面测量轨迹的数学模型,提出了一种基于独立计量回路的非接触式坐标扫描测量方法。该方法采用分离式计量框架结构,有效减少了跟踪扫描模块运动对测量精度的影响;测头采用集成阵列式波片的四象限干涉测量系统,保证测头精度的同时更有利于实现复杂面形轮廓的跟踪扫描运动;设计扫描执行机构与多路激光干涉系统共基准的运动模块,实时跟踪扫描运动机构的位置信息,提高测头空间定位精度并使其测量值能溯源到“米”定义。搭建测量装置测试该方法的准确测量精度,试验结果表明,测量误差小于0.2 μm,重复性精度为70 nm,测量精度达到亚微米级。     

Nd-YAG激光器在眼科中的应用

眼科学家是医用激光的先锋。由于眼晴的构造使它很适于激光的应用。氩激光的使用,使糖尿病视网膜病,视网膜裂孔和老年性斑样变性的治疗发生了革命性变革。近几年出现了使用超短脉冲Nd-YAG激光切割眼内组织的第二次眼科激光革命。临床应用在美国,所有短脉冲Nd-YAG激光都是在食品和医药管理局(FDA)的研究性器件许可下进行的。近来在眼科界最引人注目的Nd-YAG激光应用是用来治疗后内障混浊。当人上了年纪,或眼睛受到创伤性损伤,就可能产生白内障。通用的治疗手段是手术摘除。摘除白内障有几种不同的操作方法,而眼科越来越多地采用外囊白内障摘除。在这种手术中,囊的     

UV激光切割覆盖膜炭化问题影响因素研究

采用一种新颖的技术即在光路中首次使用光束整形器切割覆盖膜,明显的减轻了炭化现象。研究了激光切割工艺参数,抽风系统,激光器和切割材料对切割覆盖膜炭化的影响。研究表明:快的切割速度,高的激光频率,低的激光功率,可以减轻炭化。改进抽风系统,不同的激光器和切割材料,可以减轻炭化。本文研究的炭化影响因素为实际应用提供了理论和实验依据。     

抗光学损伤的深紫外膜层

准分子激光的输出特性使它能很好地适用于多种精密材料处理和生物医学应用。然而，至今对光束传输元件尤其是膜层的光学损伤始终限制着这些系统的稳定性。光学元件制造商曾致力于这一问题，将典型的膜层寿命延长了一个数量级以上。新的研究方法将抗损伤能力得到进一步的提高。图1光折变角膜切割系统使医生能用准分子激光烧蚀角膜，以修正近视眼准分子激光发展最快的应用领域是光折变角膜切割（PRK）和微细光刻。在光折变角膜切割中，一种为校正近视而进行部分切割的眼外科手术，为了确保手术成功，光束均匀性和脉冲能量必须得到严格控制。…     

面向复杂曲面的激光切割机器人移动速度平滑控制

为了提高复杂曲面下激光切割机器人的移动速度控制精度和适应能力,提出了一种面向复杂曲面的激光切割机器人移动速度平滑控制方法。通过齐次变换矩阵和D-H运动学分析方法,组建激光切割机器人运动学模型,获取机器人对应方程的正反解。采用刀具路径插补和激光入射角调整规划方法控制激光聚焦点在复杂曲面上的切割运动。同时引入加减速滤波方法修正轨迹插补后速度曲线连续性较差的问题,最终实现激光切割机器人移动速度平滑控制。仿真实验结果表明,所提方法可以有效提升激光切割机器人移动速度平滑控制精度。     

新型液相/电化学原子力显微镜的研制及其应用研究

研制了一种新型液相/电化学原子力显微镜（EC-AFM）系统。该EC-AFM系统的探头部分以激光作为光源, 设计了独特的液相光路, 采用了一块透明的玻璃作为视窗, 同时作为探针座, 将微探针和样品完全浸没在液体中进行扫描检测。设计了完全开放式的电解池, 可方便地改变样品的液体环境, 对电化学反应进行操作和控制。此外, 采取了探针扫描的方式, 使得较大和较重样品的扫描检测得以实现。利用该EC-AFM系统, 以铁片为阴极, 铜片为阳极在硫酸铜溶液中进行了化学镀铜实验, 并对实验过程进行了实时观察, 获得了不同阶段的样品表面图像。实验结果表明, 自主研制的EC-AFM在溶液中可扫描获得理想的AFM图像, 分辨率达到纳米量级, 证实该系统可以直接观察电解液中固液界面的化学反应。     

激光等离子体冲击波在眼科手术中的作用和副作用

本文根据对眼模型模拟激光手术过程的探测,研究了眼科激光手术中等离子体冲击波的产生和发展过程。根据模拟实验结果提出了等离子体冲击波在激光手术中对被治疗眼组织作用和手术中可能对周围眼组织影响的物理机理假设,可较好地解释激光眼科手术中的几种伴生现象,并在临床使用中得到了验证。     

用Nd:YAG激光切除白内障

如果应用一种新型眼科激光系统，白内障摘除手术将不必在手术室内进行，而在医生的门诊室里便可完成，巴黎的Trousseau医院的DanielleAron-Rosa博士(该激光系统的发明者)和巴尔的摩Mercy医院的Leeds Katzen博士配备了目前仅有的两台这样的系统:另一台有类似特性的激光系统,均为以He-Ne激光同轴瞄准的微微秒Nd:YAG激光器(每个脉冲3~5毫焦耳)。     

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.     

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.     

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.     

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）.