纳米压痕技术及其应用

介绍了纳米压痕技术在微机电系统、材料科学、摩擦学性能研究、生物工程和信息技术等领域中的应用 ,以及纳米压痕技术在理论研究方面的进展及今后的研究重点。

纳米技术在水处理中的应用

本文介绍纳米技术在水处理中的作用,介绍纳米TiO2光催化氧化在污水处理方面的研究进展,说明纳米膜技术在处理废水中的重要意义,指出纳米技术对水处理研究的推动及其发展前景。

咸水开发利用中的高效提取与处理技术探究

近年来,随着工业和民用对淡水资源的日益增长,对咸水资源的高效开发与利用技术受到了广泛关注。本研究主要探讨了咸水的高效提取与处理技术。通过采用现代化的分析手段,研究了咸水中各种成分的分布、性质和浓度。经过实验验证,新型的纳米滤膜技术能够在98%的回收率下,从咸水中有效地提取出92%的纯净水。同时,我们还研究了咸水中其他有价值的矿物元素的提取方法,如钾、锂等,并成功实现了其高效分离与提取。这些技术不仅为咸水资源的综合利用提供了可能,而且大大提高了淡水资源的供应能力,有助于缓解全球淡水危机。

金属污染物“锌晶须”对数据中心设备可靠性的影响与解决方案探索

针对锌晶须现象对数据中心设备构成的潜在威胁进行分析,探讨目前国外对于数据中心锌晶须危害的各种应对方案,结合行业标准对数据中心环境的要求,提出了采用环保无晶须纳米膜技术解决锌晶须隐患的方案,并以该项技术在数据中心电缆桥架上的应用为例作了详细说明。

Enhanced permeation performance of polyether-polyamide block copolymer membranes through incorporating ZIF-8 nanocrystals

Membrane-based CO_2 separation is a promising alternative in terms of energy and environmental issues to other conventional techniques. Polyether-polyamide block copolymer(Pebax) membranes are promising for CO_2 separation because of their excellent selectivity, but limited by their moderate gas permeability. In this study,fresh-prepared zeolitic imidazolate framework-8(ZIF-8) nanocrystals were integrated into the Pebax?1657matrices to form mixed matrix membranes. The resulting membrane exhibits significantly improved CO_2permeability(as high as 300% increase), without the sacrifice of the selectivity, to the pristine polymer membrane. Several physical characterization techniques were employed to confirm the good interfacial interaction between ZIF-8 fillers and Pebax matrices. The effect of added ZIF-8 fillers on the transport mechanism through MMMs is also explored. Mixed-gas permeation for both CO_2/N_2 and CO_2/CH_4 was also evaluated. The separation performance for CO_2/CH_4 mixtures on the ZIF-8/Pebax MMMs is very close to the Roberson upper bound, and thus is technologically attractive for purification of natural gas.

Process Control for Nanoimprint Lithography

To tackle the demoulding and conglutinating problem with the resist and hard mold in the nanoimprint lithography process, a soft mould can be used to demould and reduce the macro or mi- cro mismatch between mould bottom surface and wafer top surface. In nanoimprint lithography process, a mathematical equation is formulated to demonstrate the relation between the residual re- sist thickness and the pressing force during pressing the mould toward the resist-coated wafer. Based on these analytical studies, a new imprint process, which includes a pre-cure release of the pressing force, was proposed for the high-conformity transfer of nano-patterns from the mould to the wafer. The results of a series of imprint experiments showed that the proposed loading process could meet the requirements for the imprint of different patterns and feature sizes while maintaining a uniform residual resist and non-distorted transfer of nano-patterns from the mould to the resist- coated wafer.

Development of the Atomic Force Microscopy Research Technique for the Nanostructures on the Vertical Edge of Thin Insulating Film

In this work, a development of a method of a thin insulating film vertical edge visualization of metal-insulator-metal （MIM） memory cells with atomic force microscopy （AFM） using a modified Omicron UHV AFM/STM microscope was performed. This included a development of a technique of the AFM visualization of segments of a vertical edge of thin insulator SiO2 film structures on a conductive substrate, a comparison of AFM topography and current profilograms for the edge profiles, and an Omicron microscope custom upgrade. The latter allowed us to perform the AFM probe positioning to any specific area of the sample in the scanning plane by two coordinates with an order of precision of 1 micrometer. The method is illustrated with the experimental results of AFM investigations of the special MIM structures with comb-type topology, and of the cells of functioning memory matrices with 20 nm thin silicon dioxide film open edge perimeter and TiN lower electrode, including topography/current profilograms. As a conclusion, our ongoing work on the AFM visualization of a complete perimeter of a SiO2 open edge of memory cells with a special new topology with a goal to visualize conductive phase nanoparticles during switching processes is briefly overviewed.

Facile Synthesis of 3D Porous Flower-like ZnO Micro/nanostructure Films and Their Photocatalytic Performance

3D porous flower-like ZnO micro/nanostructure films grown on Ti substrates are synthesized via a very facile electrodeposition technique followed by heat treatment process. The ZnO architecture is assembled with ultra thin sheets, which consist of numbers of nanoparticles and pores, and the size of the nanoparticles can be controlled by adjusting the electrodepo- sition time or calcination temperature. It is worth noting that this synthetic method can provide an effective route for other porous metal oxide nanostructure films. Moreover, the photocatalytic performance shows the porous ZnO is an ideal photocatalyst.

Rapid nanopatterning technique based on monolayer silica nanosphere close-packing by spin coating

Nanoparticles monolayer formation by spin coating is considered to be a simple, fast and inexpensive nanopatteming technique However, the parameters that govern the overall growth process in this technique are not completely quantified and techniques for the controlled and continuous growth of close packed monolayer particle arrays without defects need to be developed. In this paper, an ordered particle array formation process is analyzed theoretically, employing material flux balance and parti- cle-subjected forces balance, based on the film thickness model of spin coating and evaporation rate law. A series of experi- ments were conducted using silica particle suspensions with various particle volume fractions and different spin speeds. The results show that the spin speed should match the particle volume fraction to meet the requirements of material flux and particles movement in order to obtain a close packed monolayer film. The formation mechanism of fabrication defects involving particle agglomeration and uncontrollable voids were analyzed qualitatively based on crystal growth theory, and validation experiments were performed. The formation of highly uniform close-packed monolayer films was demonstrated and the condi- tion requirements for achieving monolayer nanoparticles array with good quality presented.

Measurement of the thermal transport properties of dielectric thin films using the micro-Raman method

The micro-Raman method is a non-contact and non-destructive method for thermal conductivity measurement.To reduce the measurement error induced by the poor fit of the basic equation of the original micro-Raman method,we developed a new basic equation for the heat source of a Gaussian laser beam.Based on the new basic equation,an analytical heat transfer model has been built to extend the original micro-Raman method to thin films with submicrometer-or nanometer-scale thickness.Ex-periments were performed to measure the thermal conductivity of dielectric thin films with submicrometer-or nanometer-scale thickness.The thermal resistance of the interface between dielectric thin films and their silicon substrate was also obtained.The obtained thermal conductivity of silicon dioxide film is 1.23W/(m.K),and the interface thermal resistance between silicon dioxide film and substrate is 2.35×10-8m2.K/W.The thermal conductivity and interface thermal resistance of silicon nitride film are 1.07W/(m.K)and 3.69×10-8m2.K/W,respectively.The experimental results are consistent with reported data.

Light welding nanoparticles:from metal colloids to free-standing conductive metallic nanoparticle film

Bottom-up assembly of nanostructured thin films could offer an alternative low-cost approach to elec- tronic thin films. However, such solution-processed thin films are often plagued by excessive inter-particle resistance and only exhibit limited current delivering capability. Here, we report a novel approach to fabricate highly conductive free-standing metallic thin film, accomplished by combining interfacial self-assembly of nanoparticles （NPs） and a light welding process. We found that light from a xenon lamp can weld adjacent Ag and Au NPs assembled at the water-air interface, forming a highly interconnected, free-standing metallic thin film structure with excellent electrical transport properties. With such a unique structure, the resultant thin metallic films show not only high flexibility and robustness, but also high conductivity comparable to bulk metallic thin films. Our studies offer a low-cost, room-temperature, and solution-processable approach to highly conductive metallic films. It can significantly impact solution-processable elec- tronic and optoelectronic devices.