光学工艺 微细加工技术与设备

TN305.72006054700电子束光刻技术的原理及其在微纳加工与纳米器件制备中的应用=Principle of electron beamlithography and itsapplication nanofabrication and nanodevice[刊,中]/张琨(中国科学技术大学合肥微尺度物质科学国家实验室.安徽,合肥(230026)),王晓平…//电子显微学报.—2006,25(2).—97-103以几种常见的电子束曝光机为例,说明电子束光刻的工作原理和关键技术,并给出一些它在纳米器件和微纳加工方面的应用实例。图6表2参26(杨妹清)TN305.72006054701离焦写入线宽的动态高斯模型=Dynamic Gaussian modelof linewidthin defo…     

激光超衍射加工机理与研究进展

随着纳米科技和微纳电子器件的发展,制造业对微纳加工技术的要求越来越高.激光加工技术是一种绿色先进制造技术,具有巨大的发展潜力,己广泛应用于不同的制造领域.为实现低成本、高效率、大面积尤其是高精度的激光微纳加工制造,研究和发展激光超衍射加工技术具有十分重要的科学意义和应用价值.本文首先阐述了基于非线性效应的远场激光直写超衍射加工技术的原理与国内外发展状况,包括激光烧蚀加工技术、激光诱导改性加工技术和多光子光聚合加工技术等;然后介绍了几种基于倏逝波的近场激光超衍射加工技术,包括扫描近场光刻技术、表面等离子激元光刻技术等新型超衍射激光近场光刻技术的机理与研究进展;最后对激光超衍射加工中存在的问题及未来发展方向进行了讨论.     

气相沉积技术在原子制造领域的发展与应用

随着未来信息器件朝着更小尺寸、更低功耗和更高性能方向的发展,构建器件的材料尺寸将进一步缩小.传统的"自上而下"技术在信息器件发展到纳米量级时遇到瓶颈,而气相沉积技术由于其能在原子尺度构筑纳米结构引起极大关注,被认为是最有潜力突破现有制造极限进而在原子尺度构造、搭建物质形态的"自下而上"方法.本文重点讨论适用于低维材料的原子尺度制造的分子束外延技术和原子层沉积/刻蚀技术.简要介绍相关技术中蕴含的科学原理及其在纳米信息器件加工和制造领域的应用,并探讨如何在原子尺度实现对低维功能材料厚度和微观形貌的精密控制.     

强耦合串联石墨烯纳米机械振子

与微米机械振子相比, 纳米机械振子使用纳米级材料制备, 尺寸更小, 质量更轻, 它作为探测器, 在探测力、质量等物理量时拥有更高的灵敏度. 石墨烯有高强度、 低密度等优良的机械特性, 被认为是制备纳米机械振子的理想材料. 基于其制备的石墨烯纳米机械振子有着高谐振频率、高品质因子和谐振频率可调性高等优势, 对于纳米力学的基础研究和应用都具有重要的意义. 本文利用微纳加工工艺(包括电子束曝光、 电子束蒸发镀膜、 反应离子刻蚀和微米级定点干法转移技术)制备了串联石墨烯纳米机械振子样品, 并在极低温下(10 mK) 测量了石墨烯机械振子的机械性质, 实现两个串联石墨烯纳米机械振子的强耦合, 耦合强度为1.34 MHz, 协同系数C = 399.     

量子等离激元光子学在若干方向的最新进展

等离激元光子学是围绕表面等离激元的原理和应用的学科,是纳米光学的重要组成部分.表面等离激元的本质是局域在材料界面纳米尺度内的多电子元激发.这一元激发可以与电磁场强烈耦合,使得我们可以通过纳米尺度结构接收,调控和辐射微米尺度光信息,并由此衍生出等离激元光子学的诸多应用.近年来,随着纳米加工尺度逼近量子极限,等离激元的量子特性受到了广泛关注.量子尺度的等离激元承接电子的波动性和光的粒子性,以其独特的內禀属性,在量子信息、高效光电器件、高灵敏探测等方面表现出十分诱人的前景.本综述重点介绍量子等离激元近年来的发展现状,回顾相关理论的发展以及与等离激元量子特性相关的一些突破性成果.最后对量子等离激元未来的发展进行了展望.     

微纳米加工技术及其应用综述

材料与结构在微纳米尺度展现了许多不同于宏观尺度的新特征，纳米技术已经成为当前科学研究与工业开发的热门领域之一。微小型化依赖于微纳米尺度的功能结构与器件，实现功能结构微纳米化的基础是先进的微纳米加上技术，文章对微纳米加上技术做了一个综合的介绍，简要说明了微纳米加工技术与传统加工技术的区别，在微纳米加工技术的应用方面提出了一些合理选择加工技术的原则，并对当前微纳米加工技术面临的挑战和今后发展的趋势作了预测。     

近场拉曼光谱技术的发展

将近场光学技术与拉曼光谱相结合,发展出近场拉曼光谱术。综述了近场拉曼光谱探测技术的发展现状,讨论了近场拉曼光谱术的优点和纳米局域光谱分析能力。对两种常用的探测方法(常规近场光谱探测方法和近场增强拉曼光谱探测方法)进行了比较,并介绍了近场拉曼光谱技术在生物、化学、纳米材料等领域的一些应用。     

纳米云纹法实验研究

结合原子力显微镜技术提出了一种新型纳米云纹方法 ,并应用该方法进行纳米范围的变形。实验中选用原子力显微镜显示屏的扫描线做为参考栅 ,云母和高纯定向石墨的晶格结构做为试件。对纳米云纹形成原理及测量方法进行了详尽讨论。运用该方法对强脉冲激光辐照激光照射之后云母试样的剩余变形进行测量研究。成功的实验结果表明这种方法是可行性的 ,可望在纳米力学行为研究中获得广泛应用。     

金纳米颗粒阵列基底的化学置换制备及其表面增强拉曼散射特性研究

表面增强拉曼(SERS)作为一种分析手段,具有高灵敏度、高选择性、高重复性、非破坏性等优点,在过去的几十年中,被广泛应用在成分检测、环境科学、生物医药及传感器等领域。其中以金、银等贵金属纳米颗粒薄膜在表面增强拉曼(SERS)活性基底方面得到了更为广泛的应用。SERS技术一个关键的因素是如何制设计并备具有大面积、高增强能力及高重复性、可循环使用的SERS基底。通常,贵金属纳米颗粒规则阵列结构的单元颗粒电磁增强特性及其颗粒间的电磁耦合增强特性的综合作用可大力提升SERS基底的探测性能。然而,利用传统微纳米加工方法如光刻、电子束光刻等方法制备得到的贵金属纳米阵列结构的表面粗糙度不够理想。结合光刻与化学置换方法制备金纳米颗粒四方点阵列孔洞结构,并研究其作为SERS基底的电磁增强特性。具体研究利用光刻法在硅衬底上制备了规则排列的四方点阵列孔洞结构,用磁控溅射在其表面镀上金属铁膜;接着在衬底上旋涂浓度为1.893 8 mol·L-1的氯金酸液膜,在孔洞内铁和氯金酸发生置换反应,进而孔洞生成金纳米颗粒,最终得到金纳米颗粒四方点阵SERS活性基底。采用罗丹明6G(R6G)分子作为探测分子测试不同金纳米颗粒阵列结构基底的SERS谱。实验结果表明,随着化学置换反应时间的延长,金纳米颗粒排列更加紧凑有序,SERS谱增强性能更好。     

弹性发射光学制造技术研究进展

深紫外光刻、极紫外光刻和先进光源等现代光学工程需求牵引先进光学制造技术持续发展,要求超光滑光学元件表面粗糙度达到原子级水平以及表面全频段面形误差达到RMS(Root Mean Square)亚纳米量级甚至几十皮米,推动超光滑光学元件制造要求不断逼近物理极限。目前,对于如何实现上述超高精度要求的超光滑加工技术及装备仍然存在技术挑战。尤其对如何实现柱面,椭球面,超环面等复杂曲面的原子量级超光滑加工仍是国内外前沿研究方向。弹性发射加工技术是一种去除函数稳定,超低亚表面缺陷,面向原子级的超光滑加工方法,可以作为加工上述精度要求光学元件的手段。本文总结了弹性发射加工技术的国内外研究现状及最新进展,归纳了弹性发射加工技术的原理,包含流体特性、抛光颗粒运动特性和化学特性,弹性发射加工装备,影响弹性发射加工技术表面粗糙度提升和材料去除效率的因素,分析了弹性发射加工技术面临的问题,展望了未来的发展方向,期望为弹性发射加工技术进一步发展和应用提供一定的参考。     

Material transport in dip-pen nanolithography

Dip-pen na.nolithography （DPN） is a useful method for directly printing materials on surfaces with sub-50nm resolution. Because it, involves the physical transport of materials from a scanning probe tip to a surface and the subsequent chemical interaction of that material with the surface, there are many factors to consider when attempting to understand DPN. In this review, we overview the physical and chemical processes that are known to play a role in DPN, Through a detailed review of the literature, we classify inks into three general categories based on their transport properties, and highlight the myriad ways that. DPN can be used to perform chemistry at the tip of a scanning probe.     

How narrow can a meniscus be?

A water meniscus naturally forms in air between an atomic force microscope (AFM) tip and a substrate. This nanoscale meniscus produces a capillary force on the AFM, and also serves as a molecular transport channel in dip-pen nanolithography (DPN). A stable meniscus is a necessary condition for DPN and for the validity of the Kelvin equation commonly applied to AFM experiments. Lattice gas Monte Carlo simulations show that, due to thermal fluctuation, a stable meniscus has a lower limit in width. We find a minimum width of 5 molecular diameters (1.9 nm) when the tip becomes atomically sharp (terminated by a single atom).     

油墨红外光谱相似度与计算机配色精度的关系研究

为了获得高精度的配色样品,提出了一种配色方法-成分分析配色法。该方法将化学分析法与计算机配色相结合,其核心是选取与目标色成分最接近的油墨进行配色,从而实现高精度的色彩匹配,为计算机配色发展提供新的思路。与目标色成分相近的油墨配色效果验证：使用某种油墨印制目标色,并用相同的油墨进行配色,以实现目标色成分与配色色样成分的一致性。使用三个不同品牌的油墨对目标色进行配色,比较配色精度及效率。使用泗联牌三种颜色油墨以任意比例通过印刷适性仪IGT-CI(荷兰)印制目标色,这些目标色包括间色和复色,各3个色样;使用配色软件X-Rite color master(美国)建立泗联、东洋、牡丹三个品牌油墨的配色基础数据库,并对不同目标色进行配色。结果表明使用与目标色相同的泗联油墨的配色精度远高于东洋、牡丹两个品牌的油墨,配色色差整体都很小,校正1～2次就能得到小于1.0的色差,最小达到0.36,几乎实现了目标色的同色同谱匹配。实验验证了成分分析配色法的核心“选取与目标色成分最接近的油墨进行配色,可以实现高精度色彩匹配”的可行性。判别目标色与配色油墨在成分上区别的化学分析工具探讨：为了判别目标色色料与配色油墨在成分上有区别,尝试使用“红外光谱相似度”作为判别的分析工具。使用红外光谱仪Thermo Nicolet 6700(美国)测出泗联、东洋、牡丹三个品牌的三种颜色油墨的红外光谱图,使用OMNIC软件中的相关性算法得到它们与目标色油墨的红外光谱相似度,并计算出平均相似度;将各品牌油墨的红外光谱相似度与其配色实验的精度进行对比分析,评价红外光谱相似度作为化学分析判别工具的有效性。结果表明泗联牌油墨与目标色的平均红外光谱相似度为100%,东洋的为86.53%,牡丹的为64.63%。当校正次数相同时,泗联油墨配色色差最小,配色精度最高;东洋次之,是泗联油墨配色色差的2倍左右;牡丹最差,是泗联油墨配色色差的3倍以上。配色结果与其红外光谱相似度的规律是一致的,目标色油墨与配色油墨之间的红外光谱相似度越高,越容易得到高精度的配色样品。实验证明了用成分分析配色法获得高精度的色彩匹配是可行的,使用红外光谱相似度作为目标色与配色油墨在成分上的分析工具对判别配色精度是有效的。今后的工作将探讨红外光谱相似度与配色精度间的相关性数值关系,以及进一步寻求更为有效的化学分析方法来判断目标色色料与配色油墨之间的成分关系。     

Advantages of STED-Inspired 3D Direct Laser Writing for Fabrication of Hybrid Nanostructures

We present a new method of additive laser technology referred to as STED nanolithography technique. This technique provides a means for fabrication of 3D dielectric and plasmonic composite nanostructures. The new technology is of the utmost interest for the electronics manufacturing industry, in particular, for formation of specific hybrid (metal–dye) nanostructures, which can be utilized as luminescent markers in biology, medicine, criminalistics, and the trade industry. In the present study, we demonstrate the advantages of STED-inspired nanolithography for fabrication of metallic and hybrid nanostructures. The 3D-scanning setup implemented offers the possibility to form both periodic and aperiodic nanostructured arrays. We show the possibility to decrease substantially the lateral size of the lines formed with the use of STED nanolithography as compared to the direct laser writing (DLW) method. The STED nanolithography technique proposed provides a means for synthesizing metallic nanoparticles in the specified points of the volume of the studied object in vivo. In addition, we demonstrate the synthesis of metallic lines by means of STED nanolithography. Moreover, nanometer spatial precision of positioning of the synthesized nanoobjects is achieved. Therefore, it is possible to obtain significant local enhancement of the emission of luminescent markers (surface enhanced luminescence) at any desired point or area of the sample due to plasmonic enhancement of the electromagnetic fields near the surface of metallic nanostructures.     

Hyperbranched polymers – their application in printing inks

Urania^® flexographic printing ink was modified with the commercially available hyperbranched polymer Boltorn H2004. The surface tension of the printing inks was measured and the rheology behaviour of the printing inks was assessed. The flow curves (shear stress vs. shear rate) for the printing inks exhibited pseudoplastic behaviour. Modified flexographic inks were laboratory printed on three different plastic films: polyethylene, polypropylene and polyethylene terephthalate. The impact of a small amount of hyperbranched polymer on printing ink colour was examined by optical density, total colour difference ΔE ^? (CIE L ^?, a ^?, b ^?) and the gloss of the printed film. In general, the addition of the hyperbranched polymer improved the colour fastness and hardness resistance. The influence of the hyperbranched polymer on the rheological properties, optical density, CIE LAB coordinates and colour fastness is discussed.     

Adsorption of bovine serum albumin on amorphous carbon surfaces studied with dip pen nanolithography

This article reports the use of dip pen nanolithography (DPN) for the study of adsorption of bovine serum albumin (BSA) proteins on amorphous carbon surfaces; tetrahedral amorphous carbon (t-aC) and silicon doped hydrogenated amorphous carbon (a-C:H:Si). Contact angle study shows that the BSA proteins reduce the contact angle on both carbon materials. We also noticed that the drop volume dependence is consistent with a negative line tension, i.e. due to an attractive protein/surface interaction. The DPN technique was used to write short-spaced (100 nm) BSA line patterns on both samples. We found a line merging effect, stronger in the case of the a-C:H:Si material. We discuss possible contributions from tip blunting, scratching, cross-talk between lever torsion and bending and nano-shaving of the patterns. We conclude that the observed effect is caused in large measure by the diffusion of BSA proteins on the amorphous carbon surfaces. This interpretation of the result is consistent with the contact angle data and AFM force curve analysis indicating larger tip/surface adhesion and spreading for the a-C:H:Si material. We conclude by discussing the advantages and limitations of DPN lithography to study biomolecular adsorption in nanoscale wetting environments.     

Synthesis and characterization of copper ink and direct printing of copper patterns by inkjet printing for electronic devices

Among the conventional metallic inks used in the printing process, silver exhibits high conductivity and thermal stability. Nevertheless, due to the high cost of silver, it cannot be extensively used for the fabrication of inks. As a competitive alternative, copper can be considered as a substitute for silver; however, copper ink oxidizes under certain atmospheric conditions. To meet these shortcomings, a cost effective, highly conductive, and oxidation-free copper-based ink has been synthesized in this study, wherein, oxidation of the copper particles in the copper-based ink was prevented by using copper complexes. The copper ink thus fabricated was printed on chemically treated Si/SiO₂ substrates followed by the characterization of the printed copper films. The results of this study confirmed that the synthesized copper ink exhibited properties suitable for its use in the inkjet printing process for fabrication of various electronic devices.     

Mass fabrication of size-controllable hydrogel microarrays by dip-pen nanolithography with viscosity-tunable ink

A method of mass fabricating poly(ethylene glycol) (PEG) hydrogel microarrays is demonstrated. Microarrays of poly(ethylene glycol) dimethacrylate (PEG-DMA) with photoinitiator were patterned by one-dimensional (1-D) parallel dip-pen nanolithography (DPN), and the microarrays were cross-linked to form PEG hydrogels by UV irradiation in N₂ air. As an ink material for DPN printing, solid and liquid phase of PEG-DMA were mixed and prepared to tune viscosity of the ink material by temperature. Thus, the diameter of the microarrays was able to be averagely controlled from 1.7 to 6.2 μm as temperature during printing was increased from 25 °C to 37 °C, respectively. The overall microarrays showed less than 16% coefficient of variation (C.V.). Moreover, small molecules, such as fluorescence dyes, were able to be embedded in the PEG hydrogel microarrays.     

Anomalous surface diffusion in nanoscale direct deposition processes

We report the first observation of anomalous diffusion in nanometer scale direct deposition processes utilizing dip-pen nanolithography (DPN). DPN permits quite general nanostructure patterns to be drawn on flat surfaces. Here we demonstrate experimentally, and discuss theoretically, the situation in which the molecular ink in DPN binds weakly to the surface. We observe, for the weak-binding case of 1-dodecylamine on mica, that anomalous diffusion occurs, leading to nearly fractal deposition patterns.     

纳米光刻技术的现状和未来

纳米技术是21世纪信息科学的一项关键技术，纳米结构制作是纳米技术的重要组成部分，纳米光刻技术是制作纳米结构的基础，具有重要的应用前景，文章对光学光刻技术进行了概述，介绍了几种纳米光刻技术的新途径，发展现状和关键问题，最后讨论了纳米光刻技术的应用前景。