共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
利用纳米球刻蚀法制备了二维六角密排三角形银纳米阵列, 通过加入铬过渡层并改变其位置和改变金属沉积角度, 研究它们对点阵结构的影响. 实验发现, 加入铬过渡层所形成的银纳米点阵结构较无铬层有很大改善, 三角形角部更加尖锐, 更能满足传感器对信号检测的要求. 同时, 该过渡层应蒸镀在模板球排列之后, 才能获取更大面积的二维银纳米点阵结构. 在沉积角度对制备二维银纳米点阵的实验中, 基片没有旋转, 采用垂直镀膜方式更容易得到结构完整、结合较牢固、且面积较大、角部尖锐的二维银纳米点阵. 吸收光谱测量进一步验证了铬过渡层对二维银纳米点阵形貌结构的改善作用. 这些为下一步的生物修饰以及生物化学传感器的制备提供了先决条件. 相似文献
3.
M. Winzer M. Kleiber N. Dix R. Wiesendanger 《Applied Physics A: Materials Science & Processing》1996,63(6):617-619
We have applied the method of nanosphere lithography to fabricate arrays of nanometer-scale gold and cobalt particles. The individual cobalt particles were found to be in a single domain state as verified by magnetic force microscopy. By tuning the preparation conditions, we also successfully fabricated arrays of mesoscopic gold rings for the first time with potential application for persistent current experiments. 相似文献
4.
K. Morgenstern E. Laegsgaard I. Stensgaard F. Besenbacher M. Böhringer W.-D. Schneider R. Berndt F. Mauri A. De Vita R. Car 《Applied Physics A: Materials Science & Processing》1999,69(5):559-569
We investigate atomic and molecular nanostructures on metal surfaces by variable low-temperature scanning tunnelling microscopy.
In combination with molecular dynamics calculations we achieve a detailed understanding of the stability of these structures.?Atomic
nanostructures in homoepitaxial metallic systems are thermodynamically only metastable. Two-dimensional islands on Ag(110)
decay above a threshold temperature of T
l=175 K. Caused by the anisotropy of the surface, distinct decay behaviours exist above and below a critical temperature of
T
c=220 K. Calculations based on effective medium potentials of the underlying rate limiting atomic processes allow us to identify
the one-dimensional decay below T
c as well as the two-dimensional decay above T
c.?In contrast to atoms, the intermolecular electrostatic interaction of polar molecules leads to thermodynamically stable
structures. On the reconstructed Au(111) surface, the pseudo-chiral 1-nitronaphthalin forms two-dimensional supermolecular
clusters consisting predominantly of ten molecules. Comparison of images with submolecular resolution to local density calculations
elucidates the thermodynamical stability as well as the internal structure of the decamers.
Received: 25 March 1999 / Accepted: 17 August 1999 / Published online: 6 October 1999 相似文献
5.
Daoulas KCh Müller M Stoykovich MP Park SM Papakonstantopoulos YJ de Pablo JJ Nealey PF Solak HH 《Physical review letters》2006,96(3):036104
A study is presented of the self-assembly of a lamella-forming blend of a diblock copolymer and its respective homopolymers on periodically patterned substrates consisting of square arrays of spots, that preferentially attract one component, as a function of pattern dimensions and film thickness. The blend morphology follows the pattern at the substrate and forms a single quadratically perforated lamella (QPL). At intermediate film thicknesses necks connect this QPL to the film surface, resulting in a bicontinuous morphology. The necks do not register with the underlying square lattice but exhibit a substantial amount of hexagonal short-range order. For thicker films we observe bicontinuous morphologies consisting of parallel lamellae with disordered perforations. These results demonstrate a promising strategy for the fabrication of complex interfacial nanostructures from two-dimensional chemically patterned templates. 相似文献
6.
7.
8.
We fabricate the aluminum-doped zinc oxide (AZO) subwavelength gratings (SWG) on Si and glass substrates by holographic lithography and sequent CH4/H2/Ar reactive ion etching process. The etch selectivity of AZO over photoresist mask as well as the nano-scale shape is optimized for better antireflection performance. To analyze the antireflective properties of AZO SWG surface, the optical reflectivity is measured and then calculated together with a rigorous coupled-wave analysis. The reflectance spectrum can be considerably changed by incorporating the SWG into AZO film. As the SWG height of AZO on Si substrate increases, the magnitude of interference oscillations in the reflectance spectrum tends to be reduced with the larger difference between its maxima. The use of optimized SWG can significantly reduce the surface reflection of AZO film at the desired wavelengths. The measured reflectance data of AZO SWG are reasonably consistent with the simulation results. No considerable change in transmission characteristics is observed for AZO SWG structures. 相似文献
9.
Nanosphere lithography (NSL) masks were created by spin-coating of polystyrene particles onto silicon surfaces. Fluorinated hydrocarbon films were coated on the nanosphere lithography masks using plasma-enhanced chemical vapor deposition (PECVD) to obtain ordered arrays of fluorinated hydrocarbon. Atomic force microscope images show hexagonally ordered nanodots of dimension 225 ± 11 nm with a height of 23 ± 4 nm. Every hexagon encloses a circular ring of diameter 540 ± 24 nm having a height and width of 13.5 ± 0.6 nm and 203 ± 16 nm, respectively. FTIR analysis shows two distinct zones of atomic bonding of CHx and CFx in the plasma coated ordered fluorinated hydrocarbon films. 相似文献
10.
We use molecular dynamics simulations to show how 2D anchoring patterns on a substrate can be utilised to accurately control the placement and morphology of nucleating 3D nanostructures. The 2D anchoring patterns for our model system consisted of a Pt ad-atom island on a Pt substrate with a surrounding monolayer of Ag atoms. The crystallographic direction of the Pt/Ag boundaries comprising the 2D anchoring pattern and the shape of the pattern was found to have a significant effect on the resultant 3D nanostructures to the extent that one can force nanostructures to have unstable facets, changing the appearance of nanostructures completely. We used the Pt/Ag system as a model to study the effects of square, rectangular and triangular anchoring patterns on Pt(111) and Pt(100) substrates. However, the processes observed are thought to result from the successful altering of the growth mode from Frank–Van der Merwe to Volmer–Weber growth; hence, these processes should be quite general and applicable to other systems. 相似文献
11.
以自组装单层胶体小球阵列为掩模,采用直接胶体晶体刻蚀技术在硅表面制备二维有序尺寸可控的纳米结构.在样品制备过程中,首先通过自组装法在硅表面制备了直径200nm的单层聚苯乙烯(PS)胶体小球的二维有序阵列;然后对样品直接进行反应离子刻蚀(RIE),以氧气为气源,利用氧等离子体对聚苯乙烯小球和对硅的选择性刻蚀作用,通过改变刻蚀时间,制备出不同尺寸的PS胶体小球的有序单层阵列;接着以此二维PS胶体单层膜为掩模,以四氟化碳为气源对样品进行刻蚀;最后去除胶体球后得到二维有序的硅柱阵列.SEM和AFM的测量结果表明:改变氧等离子体对胶体球的刻蚀时间和四氟化碳对硅的刻蚀时间,可以控制硅柱的尺寸以及形貌,而硅柱阵列的周期取决于原始胶体球的直径.
关键词:
胶体晶体刻蚀
纳米硅柱阵列 相似文献
12.
S. Sepulveda-Guzman B. Reeja-Jayan U. Ortiz-Mendez R. Cruz-Silva 《Applied Surface Science》2010,256(11):3386-6820
In this work patterned ZnO films were prepared at room-temperature by deposition of ∼5 nm size ZnO nanoparticles using confined dewetting lithography, a process which induces their assembly, by drying a drop of ZnO colloidal dispersion between a floating template and the substrate. Crystalline ZnO nanoparticles exhibit a strong visible (525 nm) light emission upon UV excitation (λ = 350 nm). The resulting films were characterized by scanning electron microscopy (SEM) and atomic force microscope (AFM). The method described herein presents a simple and low cost method to prepare crystalline ZnO films with geometric patterns without additional annealing. Such transparent conducting films are attractive for applications like light emitting diodes (LEDs). As the process is carried out at room temperature, the patterned crystalline ZnO films can even be deposited on flexible substrates. 相似文献
13.
J.P. Kar 《Applied Surface Science》2009,255(7):4087-4092
ZnO nanostructures were grown on silicon, porous silicon, ZnO/Si and AlN/Si substrates by low-temperature aqueous synthesis method. The shape of nanostructures greatly depends on the underlying surface. Scattered ZnO nanorods were observed on silicon substrate, whereas aligned ZnO nanowires were obtained by introducing sputtered ZnO film as a seed layer. Furthermore, both the combination of nanorods and the bunch of nanowires were found on porous silicon substrates, whereas platelet-like morphology was observed on AlN/Si substrates. XRD patterns suggest the crystalline nature of aqueous-grown ZnO nanostructures and high-resolution transmission electron microscopy images confirm the single-crystalline growth of the ZnO nanorods along [0 0 1] direction. Room-temperature photoluminescence characterization clearly shows a band-edge luminescence along with a visible luminescence in the yellow spectral range. 相似文献
14.
采用纳米球刻蚀(nanosphere lithography)技术,以自组装的聚苯乙烯纳米小球(polystyrene,PS小球)的单层膜为掩模,制备出二维有序的CdS纳米阵列.利用扫描电子显微镜(SEM)对样品结构进行了表征,用紫外—可见分光光度计对样品光学性质进行了分析.结果表明:制备的二维CdS纳米阵列是高度有序的,且与作为掩模的纳米小球的原始尺寸及排布结构一致;禁带宽度为2.60eV,相对于体材料的2.42eV,向短波长蓝移了0.18eV,表现出CdS材料在纳米结构点阵中的量子尺寸效应;CdS纳米
关键词:
纳米球刻蚀
二维CdS纳米有序阵列 相似文献
15.
Zhenyang Zhong Gang Chen J. Stangl Th. Fromherz F. Schffler G. Bauer 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):588
Stacks of Ge islands layers, separated by thin Si spacer layers, have been grown on prepatterned Si (0 0 1) substrates. The sample topography, obtained by atomic force microscopy, exhibits a regular two-dimensional island arrangement. The vertical alignment is confirmed in cross-sectional transmission electron microscopy images. X-ray diffraction reciprocal space maps around the (0 0 4) Bragg point reveal exceptional lateral and vertical ordering of the Ge islands. Photoluminescence spectra taken at 5 K show well-separated peaks of the no-phonon and the transverse-optical phonon replica of these ordered islands, which is achieved too, due to the excellent island size uniformity. 相似文献
16.
Shengli Huang Lingqi Kong Chunjing Zhang Yan Wu Xianfang Zhu 《Physics letters. A》2011,375(33):3012-3016
Effect of chromium interlayer deposition on 2-dimensional, periodic silver nanoparticle array structure was systematically investigated. The silver nanoparticle array was fabricated by nanosphere lithography with assembled polystyrene nanospheres being as a deposition mask. The chromium interlayer was deposited by thermal evaporation either on the nanosphere mask or directly on the silicon substrate. The structures of the achieved silver nanoparticle arrays were characterized by scanning electron microscope and were compared with that of silver nanoparticle array without the interlayer. With analysis of the anomalies among the structures the critical role of the interlayer in the periodic nanoparticle array fabrication was revealed. 相似文献
17.
Wei Li Wei-Ming Zhao Ping Sun Xin-Fan Huang Kun-Ji Chen 《Applied Surface Science》2007,253(22):9035-9038
We present a fabrication procedure that can form large-scale periodic silicon nanopillar arrays for 2D nanomold which determines the feature size of nanoimprint lithography, using modified nanosphere lithography. The size of silicon nanopillars can be easily controlled by an etching and oxidation process. The period and density of nanopillar arrays are determined by the initial diameter of polystyrene (PS) spheres. In our experiment, the smallest nanopillar has a full width half maximum (FWHM) of approximately 50 nm, and the density of silicon pillar is ∼109/cm2. Using this approach, it is possible to fabricate 2D nanoimprint lithography mask with 50 nm resolution. 相似文献
18.
Nanosphere lithography (NSL) is a successful technique for fabricating highly ordered arrays of ZnO nanowires typically on sapphire and GaN substrates. In this work, we investigate the use of thin ZnO films deposited on Si by pulsed laser deposition (PLD) as the substrate. This has a number of advantages over the alternatives above, including cost and potential scalability of production and it removes any issue of inadvertent n-type doping of nanowires by diffusion from the substrate. We demonstrate ordered arrays of ZnO nanowires, on ZnO-coated substrates by PLD, using a conventional NSL technique with gold as the catalyst. The nanowires were produced by vapor phase transport (VPT) growth in a tube furnace system and grew only on the areas pre-patterned by Au. We have also investigated the growth of ZnO nanowires using ZnO catalyst points deposited by PLD through an NSL mask on a bare silicon substrate. 相似文献
19.
Sergei F. Lyuksyutov Mindaugas RackaitisVictoria Nedashkivska 《Applied Surface Science》2011,257(10):4581-4585
A nanolithography technique based on the lateral displacement of electrically biased AFM tip was developed for nanostructures formation of 30-100 nm in width and 1-10 nm in height in the polystyrene (PS) films. It was demonstrated that the nanostructures patterned in annealed PS films (90K Mw) show slow exponential relaxation between 55 and 265 h depending on their size. Relaxation of the nanostructures in non-annealed films usually occurred in minutes. It was observed that in the annealed samples a negative electric charge accumulated in the areas where the nanostructures formed while in the non-annealed samples only the positive charge in exposed areas was detected using the electric force microscopy. After 320 h of monitoring under the humidity maintained between 25 and 27% it was suggested that slow dynamical changes of the nanostructures can be attributed to the negative electric charge dissipation in the annealed samples. 相似文献
20.
Fabrication of metal oxide nanostructures based on Atomic Force Microscopy lithography 总被引:1,自引:0,他引:1
XiaoYang Zhu Gang Cheng ShuJie Wang ShuXi Dai ShaoMing Wan XingTang Zhang ZuLiang Du 《中国科学G辑(英文版)》2008,51(10):1448-1454
Atomic Force Microscopy (AFM) mechanical lithography is a simple but significant method for nanofabrication. In this work,
we used this method to construct nanostructures on Pt/Cu bilayer metal electrodes under ambient conditions in air. The influence
of various scratch parameters, such as the applied force, scan velocity and circle times, on the lithography patterns was
investigated. The Pt-Cu-Cu
x
O-Cu-Pt nanostructure was constructed by choosing suitable scratch parameters and oxidation at room temperature. The properties
of the scratched regions were also investigated by friction force microscopy and conductive AFM (C-AFM). The I–V curves show symmetric and linear properties, and Ohmic contacts were formed. These results indicate that AFM mechanical lithography
is a powerful tool for fabricating novel metal-semiconductor nanoelectronic devices.
Supported by the National Natural Science Foundation of China (Grant No. 90306010), the Program for New Century Excellent
Talents in University of China (Grant No. NCET-04-0653), the National Basic Research Program of China (Grant No. 2007CB616911),
and the Science and Technology Department of Henan Province (Grant No. 072300420100) 相似文献