一种检测光刻机激光干涉仪测量系统非正交性的新方法

提出一种精确检测光刻机激光干涉仪测量系统非正交性的新方法。将对准标记曝光到硅片表面并进行显影;利用光学对准系统测量曝光到硅片上的对准标记理论曝光位置与实际读取位置的偏差;由推导的位置偏差与非正交因子、坐标轴尺度比例、过程引入误差的线性模型,根据最小二乘原理计算出干涉仪测量系统的非正交性。实验结果表明,利用该方法使用同一硅片在不同旋转角下进行测量,干涉仪测量系统非正交因子的测量重复精度优于0.01 μrad,坐标轴尺度比例的测量重复精度优于0.7×10-6。使用不同的硅片进行测量,非正交因子的测量再现性优于

Coma measurement by use of an alternating phase-shifting mask mark with a specific phase width

The correlation between the coma sensitivity of the alternating phase-shifting mask (Alt-PSM) mark and the mark's structure is studied based on the Hopkins theory of partially coherent imaging and positive resist optical lithography (PROLITH) simulation. It is found that an optimized Alt-PSM mark with its phase width being two-thirds its pitch has a higher sensitivity to coma than Alt-PSM marks with the same pitch and the different phase widths. The pitch of the Alt-PSM mark is also optimized by PROLITH simulation, and the structure of p - 1.92 lambda/NA and pw = 2p/3 proves to be with the highest sensitivity. The optimized Alt-PSM mark is used as a measurement mark to retrieve coma aberration from the projection optics in lithographic tools. In comparison with an ordinary Alt-PSM mark with its phase width being a half its pitch, the measurement accuracies of Z(7) and Z(14) apparently increase. (C) 2009 Optical Society of America

模块化蓝光光存储性能静态测试系统

蓝光光存储是信息存储领域发展的一个重要方向。测试系统是研究蓝光光存储材料的必备条件，为建立蓝光光存储研究平台，设计和搭建了一套模块化蓝光光存储性能静态测试系统。激光工作波长为406．7nm。系统采用调制解调技术降低系统噪声，提高测量粘度：采用光点移动模式降低对样品尺寸的要求；采用纳米平台提高记录点的反复定位性能。实验结果证明测试系统性能良好，可以满足蓝光光存储性能静态测试要求。

Investigation on the static recording characteristic of super-resolution near-field structure with antimony mask layer

Static recording characteristic of super-resolution near-field structure with antimony (Sb) is investigated in this paper. The recording marks are observed by a scanning electron microscopy (SEM), a high-resolution optical microscopy with a CCD camera and an atomic force microscopy (AFM). The super-resolution mechanism is also analyzed based on these static recording marks. Results show that the light reaching on recording layer is composed of two parts, one is the linear transmissive light (propagating field) and the other is the nonlinear evanescent light in the optical near field. The evanescent light may be greatly enhanced in the center of the spot because Sb will transit from a semiconductor to a metal when it is melted under the high laser power irradiation. This local melted area in the spot center may be like a metal tip in the optical near field that can collect and enhance the information that is far beyond the diffraction limit, which leads to the super-resolution recording and readout. (c) 2005 Elsevier Ltd. All rights reserved.

Design and construction of a static tester for blue ray optical storage

Blue ray optical storage is one of the important trends in the area of information storage, and attracts a number of researchers. Static tester for blue ray optical storage plays an important role in storage media research. We designed and constructed a static tester, in which modularization makes it very convenient to expand function. Employment of modulation/demodulation technique weakens test error so as to increase test precision. Focus move mode and the nano-positioners facilitate the relocation of recording marks. Only one laser with wavelength 406.7 nm is used. In this paper, system design and characteristics are represented in detail, and some experimental results are also given to show that the static tester can perform successfully, acting as research platform for blue ray optical storage. (c) 2005 Elsevier GmbH. All rights reserved.

Optical parameters and absorption of copper (II)-azo complexes thin films as optical recording media

Smooth thin films of three kinds of azo dyes of 2-(5'-tert-butyl-3'-azoxylisoxazole)-1, 3-diketones and their copper (II)-azo complexes were prepared by the spin-coating method. Absorption spectra of the thin films on a glass substrate in the 300-600 nm wavelength region were measured. Optical constants (complex refractive index N=n+ik) and thickness of the thin films prepared on single-crystal silicon substrate in the 300-600 nm wavelength region were investigated on rotating analyzer-polarizer type of scanning ellipsometer, and dielectric constants epsilon(epsilon=epsilon(1)+i epsilon(2)), absorption coefficients alpha as well as reflectance R of thin films were then calculated. In addition, one of the copper (II)-azo complex thin film prepared on glass substrate with an Ag reflective layer was also studied by atomic force microscopy (AFM) and static optical recording. AFM study shows that the copper (II)-azo complex thin film is very smooth and has a root mean square surface roughness of 1.89 nm. Static optical recording shows that the recording marks on the copper (II)-azo complex thin film are very clear and circular, and the size of the minimal recording marks can reach 200 nm. (c) 2004 Elsevier B.V. All rights reserved.

SbOx thin films used for write-once blue laser recording

SbOx thin films are deposited by reactive dc-magnetron sputtering from all antimony metal target in Ar+O-2 with the relative O-2 content 7%. It is found that the as-deposited films call represent a two-component system comprising amorphous Sb and amorphous Sb2O3. The crystallization of Sb is responsible for the changes of optical properties of the films. The results of the static, test show that the SbOx thin films have good writing sensitivity for blue laser beams and the recording marks are very clear and circular. High reflectivity contrast of about 41% is obtained at a writing power 6 mW and writing pulse width 300 ns. In addition, the films show a good stability after reading 10000 times.

Write-once blue laser recording using silicon doped SbOx thin films prepared by reactive dc-magnetron sputtering

Si:SbOx films have been deposited by reactive dc-magnetron sputtering from a Sb target with Si chips attached in Ar + O-2 with the relative O-2 content 7%. The as-deposited films contained Sb metal, Sb2O3, SiO, Si2O3 and SiO2. The crystallization of Sb was responsible for the changes of optical properties of the films. The results of the blue laser recording test showed that the films had good writing sensitivity for blue laser beam (406.7 nm), and the recording marks were still clear even if the films were deposited in air 60 days, which demonstrated that doping silicon in SbOx films can improve the stability of SbOx films. High reflectivity contrast of about 36% was obtained at a writing power 6 mW and writing pulse width 300 ns. (c) 2007 Elsevier B.V. All rights reserved.

Optical properties of nickel(II)-azo complexes thin films for potential application as high-density recordable optical recording media

Smooth thin films of three kinds of nickel(II)-azo complexes were prepared by the spin-coating method. Absorption spectra of the thin films on K9 glass substrate in the 300-600 nn wavelength region were measured. Optical constants (complex refractive index N = n + ik) and thickness of the thin films prepared on single-crystal silicon substrate in the 300-600 nm wavelength region were investigated on rotating analyzer-polarizer type of scanning ellipsometer, and dielectric constants epsilon (epsilon = epsilon(1) + i epsilon(2)), absorption coefficients a as well as reflectance R of thin films were then calculated at 405 nm. In addition, in order to examine the possible use of nickel(II)-azo complex thin film as an optical recording medium, one of the nickel(II)-azo complex thin film prepared on K9 glass substrate with an Ag reflective layer was also studied by atomic force microscopy and static optical recording. The results show that the nickel(II)-azo complex thin film is smooth and has a root mean square surface roughness of 2.25 nm, and the recording marks on the nickel(II)-azo complex thin film are very clear and circular, and their size can reach 200 nn or less. (c) 2006 Elsevier Ltd. All rights reserved.

Write-once medium with Fe-Doped BiOx thin films for blue laser recording

Fe:BiOx films are fabricated on K9 glass substrates by rf-magnetron sputtering of a BiFeO target under argon atmosphere with increasing sputtering power from 80 to 200 W at room temperature. It is found that the thin films grown at the sputtering power of 160W can be formed at an appropriate deposition rate and have an improved surface morphology. The XPS result reveals that the films investigated are comprised of Bi, Fe and O elements. A typical XRD pattern shows that no phase transition occurs in the films up to 400 degrees C. The results of the blue laser recording test demonstrate that the Fe:BiOx films have good writing sensitivity for blue laser beam (406.7 nm) and good stability after reading 10000 times. The recording marks of 200nm or less are obtained. These results indicate that the introduction of Fe into BiOx films can reduce the mark size and improve the stability of the films.

The ADH1B Arg47His polymorphism in East Asian populations and expansion of rice domestication in history

Background: The emergence of agriculture about 10,000 years ago marks a dramatic change in human evolutionary history. The diet shift in agriculture societies might have a great impact on the genetic makeup of Neolithic human populations. The regionally restricted enrichment of the class I alcohol dehydrogenase sequence polymorphism (ADH1BArg47His) in southern China and the adjacent areas suggests Darwinian positive selection on this genetic locus during Neolithic time though the driving force is yet to be disclosed. Results: We studied a total of 38 populations (2,275 individuals) including Han Chinese, Tibetan and other ethnic populations across China. The geographic distribution of the ADH1B*47His allele in these populations indicates a clear east-to-west cline, and it is dominant in south-eastern populations but rare in Tibetan populations. The molecular dating suggests that the emergence of the ADH1B*47His allele occurred about 10,000 similar to 7,000 years ago. Conclusion: We present genetic evidence of selection on the ADH1BArg47His polymorphism caused by the emergence and expansion of rice domestication in East Asia. The geographic distribution of the ADH1B*47His allele in East Asia is consistent with the unearthed culture relic sites of rice domestication in China. The estimated origin time of ADH1B*47His allele in those populations coincides with the time of origin and expansion of Neolithic agriculture in southern China.

Variables affecting melanoidins removal from molasses wastewater by coagulation/flocculation

Coagulation/flocculation process was applied in the polishing treatment of molasses wastewater on a bench-scale. Important operating variables, including coagulant type and dosage, solution pH, rapid mixing conditions as well as the type and dosage of polyeletrolytes were investigated based on the maximum removal efficiencies of chemical oxygen demand (COD) and color, residual turbidity and settling characteristics of flocs. HPSEC was utilized to evaluate the removal of molecular weight fractions of melanoidins-dominated organic compounds. Experimental results indicate that ferric chloride was the most effective among the conventional coagulants, achieving 89% COD and 98% color eliminations; while aluminum sulfate was the least effective, giving COD and color reductions of 66% and 86%, respectively. In addition to metal cations, counter-ions exert significant influence on the coagulation performance since Cl--based metal salts attained better removal efficiency than SO42--based ones at the optimal coagulant dosages. Coagulation of molasses effluent is a highly pH-dependent process, with better removal efficiency achieved at lower pH levels. Rapid mixing intensity, rather than rapid mixing time, has relatively strong influence on the settling characteristics of flocs formed. Lowering mixing intensity resulted in increasing settling rate but the accumulation of floating flocs. When used as coagulant aids, synthetic polyelectrolytes showed little effects on the improvement in organic removal. On the other hand, cationic polyacrylamide was observed to substantially enhance the settleability of flocs as compared to anionic polyacrylamide. The effects of rapid mixing conditions and polymer flocculants on the coagulation performance were discussed. (C) 2009 Elsevier B.V. All rights reserved.

猕猴体细胞核移植影响因素的研究：着床前胚胎表观遗传重编程和供体细胞周期同步化

体细胞核移植（somatic cell nuclear transfer）克隆技术的成功，特别 是运用终末分化的淋巴细胞和嗅觉神经元细胞成功克隆出小鼠，证实了分化的体 细胞核潜在的发育全能性。该技术已经在多个物种上成功地得到克隆后代，在转 基因动物、基因敲除动物和疾病模型动物生产中也得到成功应用，在结合干细胞 技术的治疗性克隆和再生医学方面也取得了初步成果，展现出了具有深远意义的 应用前景。但是，目前该领域仍然存在着很多急待解决的重要问题：克隆成功率 低，克隆胚和克隆动物经常呈现发育异常，妊娠和出生前后的高死亡率。对哺乳 动物早期胚胎发育过程中DNA 甲基化、组蛋白修饰等表观遗传重编程 （epigenetic reprogramming）机制的深入了解，有助于研究体细胞核在去核卵 母细胞中的表观遗传重编程事件，进而改善克隆胚重编程效率和发育能力。 猕猴是一种重要的实验动物，在人类疾病模型和生物医药研究中有重要的意 义。本研究主要围绕猕猴体细胞克隆胚胎早期发育过程中的表观遗传重编程事件 和核移植前体细胞同步化处理这两方面展开。1），首次详细地了描绘了猕猴着床 前胚胎发育过程中整体水平的DNA 甲基化表观遗传重编程事件，研究发现在受精 卵中父本基因组形成原核后迅速地发生了去甲基化，在2 细胞期后的卵裂过程 中，母本基因组才开始逐渐地去甲基化，到桑葚胚达到最低水平，然后开始重新 （de novo）甲基化,到囊胚期时形成不对称的甲基化模式，滋养外胚层（TE）呈 现高甲基化状态，而内细胞团（ICM）呈现低甲基化状态,这一不对称模式可能是 灵长类动物特有的，其他哺乳动物呈现正好相反的不对称模式。2），研究发现， 大多数猕猴克隆胚胎的DNA 甲基化重编程存在异常,效率低。很多2 细胞期克隆 胚（67%）和8 细胞期克隆胚（50%）的核DNA 甲基化水平显著高于对应的体 外受精胚，8 细胞克隆胚之间呈现多种不同的表观遗传特征。大多数克隆囊胚的 ICM 细胞核的甲基化水平显著高于IVF 囊胚，这些异常可能是导致克隆胚胎移 植到代孕母体后发育时间不长就失败的原因。3），在核移植前对猕猴成纤维细 胞同步化处理的研究中发现，血清饥饿，细胞周期阻断剂DMSO（二甲基亚砜）、 roscovitine、aphidicolin 和indirubin 的处理都有显著的同步化效果，提高了G0+G1 期细胞的比例。经过BrdU 标记法证实了这几种处理方法抑制细胞增殖的效果，并且证实了这种周期阻滞作用是可逆的。用原位末端标记法（TUNEL）分析证 实，血清饥饿1 到4 天后细胞凋亡比例显著上升，在贴壁的细胞中约有6%发生 凋亡，而正常对照只有1%左右，而周期阻断剂处理没有增加细胞凋亡率，这提 示这些周期阻断剂可能是一种相对安全且有效的猕猴成纤维细胞处理方法。核移 植前对猕猴成纤维细胞进行处理，有助于优化体细胞核移植技术，也是改善体细 胞核在克隆胚中重编程效率的重要途径。

克拉维酸产生菌的诱变育种与发酵工艺优化研究

以克拉维酸产生菌棒状链霉菌Streptomyces clavuligerus CCRC11518（ATCC 27064）III50为出发菌株, 首先比较各种物理和化学诱变剂处理对其克拉维酸生物合成的影响, 确定了亚硝基胍为棒状链霉菌诱变育种的诱变剂及其处理剂量: 2mg/ml、40min. 经浓度为2mg/ml的亚硝基胍处理40min后, 采用新颖理性化筛选方法, 通过逐步筛选自身代谢产物抗性突变株、克拉维酸抗性突变株和链霉素抗性突变株, 最终得到一株克拉维酸高产菌VI118(效价633μg/ml), 其克拉维酸效价是出发菌株(效价377μg/ml)的167.9%. 该高产突变株在琼脂斜面培养基上连续传接10代, 克拉维酸效价保持稳定. 通过单因子和多因子摇瓶正交试验, 对高产菌株VI118的发酵条件进行了研究, 确定最佳发酵条件: 甘油60g, 水解植物蛋白 60g, KH2PO4 0.5 g, 玉米浆 7.5g, MnSO4•H2O 0.34g, MgSO4•7H2O 0.99g, FeSO4•7H2O 0.56g, 蒸馏1000ml, pH 7.0, 发酵培养基装量20ml/250ml三角瓶, 接种量10％, 培养温度28ºC, 220r/min摇床培养72h后测定效价. 在最佳发酵条件下克拉维酸效价达到651μg/ml, 同时把初始发酵培养基的昂贵成分替换为廉价的工业原料. 通过摇瓶分批补料试验, 得到最佳补料物质和补料方式：在上述最佳发酵条件下, 分别在发酵培养48h、56h、64h、72h时补加4ml无菌水, 80h发酵结束, 克拉维酸效价达到905μg/ml. 在不增加原料成本的情况下通过摇瓶补料方式克拉维酸效价为未补料的139.0％, 总产量为未补料的264％. By a novel rational screening method, mutant Streptomyces clavuligerus CCRC11518（ATCC 27064）III50（titres 377μg/ml）, as the clavulanic acid-producing parent strain, was treated by NTG (2mg/ml) for 40min, and the self-generated metabolites resistant mark, the clavulanic acid resistant mark and the streptomycin resistant mark were added step by step. Finally, the mutant VI118（titres 633μg/ml）with the three marks was obtained. The clavulanic acid productivity of this mutant was increased by 167.9% compared with the parent strain. After reproducing 10 generations on the agar medium slant, the productivity of this mutant was stable. The optimum fermentation conditions were established as followings: glycerol 60g, acid hydrolyzed vegetable protein 60g, KH2PO4 0.5g, corn steep liquor 7.5g, MnSO4•H2O 0.34g, MgSO4•7H2O 0.99g, FeSO4•7H2O 0.56g, distilled water 1 liter, pH 7.0, 20ml in 250ml shake-flask, inoculation 10%(v/v), fermentation temperature 28ºC, rotation speed 220 r/min, time 72h. The clavulanic acid productivity was 651μg/ml, while used the low-priced industrial raw materials. After studying on fed-batch in the shake-flask, the optimum fed-batch manner was obtained: under optimum fermentation conditions, at 48h, 56h, 64h and 72h, adding 4ml distilled water into each flask, fermentation ending at 80h. The clavulanic acid productivity was increased by 139% compared with no fed-batch, meanwhile the total yield was increased by 264%.

Development of external electron-beam enhancement of the Penning ionization gauge ion source

To study the injection of additional electrons from an external electron gun into the plasma of a Penning ionization gauge (PIG) ion source, a test bench for the external electron-beam enhancement of the PIG (E-PIG) ion source was set up. A source magnet assembly was built to satisfy the request for magnetic field configuration of the E-PIG ion source. Numerical calculations have been done to optimize the magnetic field configuration so as to fit the primary electrons to be fed into the PIG discharge chamber along the spreading magnetic field lines. Many possible methods for improving the performance and stability of the PIG ion source have been used in the E-PIG ion source, including the use of multicrystal LaB6 cathode and optimized axial magnetic field. This article presents a detailed design of the E-PIG ion source. Substantial enhancement of ion charge state is expected to be observed which demonstrates that the E-PIG is a viable alternative to other much more costly and difficult to operate devices for the production of intense ion beams of higher charge state.