用于纳米光刻的超分辨缩小成像平板超透镜研究

本文提出和研究了利用超分辨缩小成像平板超透镜,在i线光源波长下实现纳米尺度光刻方法.为了在超 分辨透镜像面位置获得高质量的光刻图形,采用超分辨透镜-光刻胶-反射银膜的结构方式,解决由于超透镜磁场偏振传输模式带来的成像光场畸变问题,大大提高了成像质量和光场对比度.采用掩模图形结构预补偿的方法,消除超分辨透镜的倍率畸变像差...     

透镜阵列光刻法消差原理分析

透镜阵列光刻法用一个柱面阵列透镜代替常规光刻法中的柱面透镜形成光程差,将由衍射所引起的瞬变图形错开,消除由于光刻模板与被刻光栅之间因间隙引起的衍射误差。用光学传递函数方法说明了透镜阵列消除光刻中衍射误差的原理。实验表明透镜阵列光刻法,可以较好的消除衍射误差,研制出高质量的光栅。     

SU—8的紫外深度光刻模拟

在微电子机械系统（MEMS）中，大高宽比微结构被广泛应用，由于紫外光衍射效应比较大，通过紫外光刻获得高精度的大高度微结构并不容量，本主要研究了衍射效应对深紫外光刻精度的影响，并与实验结果进行了比较，理论模拟结果和实验比较吻合，因此，通过模拟结果得到不同厚度光刻胶的最佳曝光剂量，以便得到更好的微结构图形。     

用灰度曝光技术改善数字光刻图形轮廓

基于空间光调制器(SLM)数字光刻技术可用于IC掩模制作或直接作为微结构的加工工具,但用数字投影光刻系统加工某些结构的二元图形时,往往难以获得预期的图形轮廓,即图形边缘处有一定畸变,特别是较低缩小倍率时。本文提出优化设计图形边缘灰度的方法来校正光刻图形的畸变。文中分析了数字光刻制作这些二元光刻图形时空间像畸变产生的物理机制,详细讨论了设计图形边缘灰度优化的规则,并以加工圆孔滤波器为例,模拟了它的数字光刻成像过程。结果表明,设计图形的边缘采用灰度曝光可使其空间像畸变减小约8个百分点,光场分布更为均匀。数字灰度曝光技术简单易行,可为改善光刻图形质量提供了新途径。     

SU-8的紫外深度光刻模拟

在微电子机械系统 (MEMS)中 ,大高宽比微结构被广泛应用。由于紫外光衍射效应比较大 ,通过紫外光刻获得高精度的大高度微结构并不容易。本文主要研究了衍射效应对深紫外光刻精度的影响 ,并与实验结果进行了比较 ,理论模拟结果和实验比较吻合。因此 ,通过模拟结果得到不同厚度光刻胶的最佳曝光剂量 ,以便得到更好的微结构图形     

微光刻相移掩模技术研究

本文系统地论述了提高光刻分辨率的相移掩模技术的基本原理、计算模拟和光刻曝光实验 ;给出了模拟和实验结果 ;研究表明 ,只有在一定的临界参数条件下 ,相移掩模才能明显地改善分辨率和工艺宽容度 ;采用无铬相移掩模得到了 0 .2 μm的清晰抗蚀剂图形 ,证明了相移掩模在提高光刻分辨率、延长光刻技术寿命以及推进光刻技术极限发展方面的优良性能     

相移掩模方法及其一维数值模拟

相移掩模方法是一种新的光刻技术，它可以提高现有光刻设备的分辨率，使超大规模集成电路及二元光学的制作迈上一个新台阶。本文介绍了相移掩模方法的基本原理，用部分相干光成象理论分析了用于光刻的投影照相系统的成象特性，导出了一维成象的简化公式，对一维光栅结构进行了计算机数值模拟并给出了模拟结果。     

掩模投影成像干涉光刻研究

掩模投影成像干涉光刻技术以在很小或几乎不增加光刻系统成本的基础上来提高光刻分辨率为目的,充分利用系统的有限孔径,将掩模图形不同的空间频率分别进行传递,最终以高分辨率对掩模成像。本文阐述了IIL的基本原理,介绍了一种实验系统,并给出了部分模拟和实验结果。研究结果表明,掩模投影成像干涉光刻技术比传统投影光刻能够得到更高的光刻分辨率。     

用于大面积周期性图形制造的激光干涉光刻

用两束或多束相干激光束以不同的组合形式对光致抗蚀剂曝光,可在大面积范围内产生精细的二维周期性图形,这个方法特别适合于产生光电子器件和生电子器件的周期性结构。介绍激光干涉光刻的基本原理,对几种光束组合干涉方法给出了理论推导结果,并进行了计算机模拟。初步的实验结果表明,用激光干扰光刻技术产生大面积的亚微米级周期性孔、柱、锥图形是可行的。该方法不需要掩模、昂贵的光刻成像透镜、新的短波长光源和新型的抗蚀剂,提供了得到高分辨、无限焦深、大面积光刻的可能性。     

环氧基负性光刻胶加工微结构的试验研究

在正交试验的基础上,将BP神经网应用于负性光刻胶(SU-8)加工高分辨率和高深宽比微结构的工艺研究,建立了光刻图形质量与前烘时间、前烘温度、曝光量、后烘时间之间的预测模型,该模型采用三层前向网络,学习算法为梯度下降法。通过实验,得出:前烘温度与前烘时间对光刻质量影响最大,对120～340μm厚的光刻胶,前烘温度取90℃,前烘时间50~100min时,图形的相对线宽差最小;最佳后烘时间(85～95℃)为30min;超声搅拌能缩短显影时间,改善图形质量。试验结果与网络预测结果吻合。结果表明,将BP神经网络应用于UV-LIGA技术中,可以优化光刻工艺。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Effect of Oxide Assisted Metal Nanoparticles on Microstructure and Morphology of Gallium oxide Nanowires

Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from