Nanometer-scale patterns have been created in self-assembled monolayers by using a scanning near-field optical microscope coupled to an ultra-violet laser emitting light at wavelength of 244 nm. Sharp, chemically well-defined features with dimensions as small 40 nm routinely, and on occasions line widths 25 (λ/10) achieved. Because the wide range photochemical methods available for surface derivatization, this approach promises provide flexible versatile route generation molecular biological...

The UV photo-oxidation of oligo(ethylene glycol) (OEG)-terminated self-assembled monolayers (SAMs) has been studied using static secondary ion mass spectrometry, X-ray photoelectron spectroscopy, contact angle measurement, and friction force microscopy. OEG-terminated SAMs are oxidized to yield sulfonates, but photodegradation the OEG chain also occurs on a more rapid time scale, yielding degradation products that remain bound surface via gold−sulfur bonds. oxidation these is rate-limiting...

Directed self-assembly of nanoparticles (DSA-n) holds great potential for device miniaturization in providing patterning resolution and throughput that exceed existing lithographic capabilities. Although excel at assembling into regular close-packed arrays, actual devices on the other hand are often laid out sparse complex configurations. Hence, deterministic positioning single or few particles specific positions with low defect density is imperative. Here, we report an approach DSA-n...

Friction force microscopy (FFM) is a technique based upon scanning that provides information on the properties of molecular materials. Continuum mechanics models may be used to conduct quantitative analyses data. While there are some important unresolved issues associated with contact tip–sample interaction, growing body data demonstrates sensitivity FFM changes in organisation and surface composition. Importantly, these nm spatial resolution, making it many respects unique tool for...

Nanostructures of metal sulfides are conventionally prepared via chemical techniques and patterned using self-assembly. This poses a considerable amount challenge when arbitrary shapes sizes nanostructures desired to be placed at precise locations. Here, we describe an alternative approach nanoscale patterning zinc sulfide (ZnS) directly spin-coatable electron beam sensitive butylxanthate resist without the lift-off or etching step. Time-resolved damage studies micro-Raman micro-FTIR...

The efficiency of chemical biocides as anti-bacterial agents is well documented and there are various methods to incorporate these bactericidal onto commonly used substrates, such textile materials. Silver known for its excellent inhibitory properties due direct action on the morphology cellular membrane bacteria. use silver is, however, limited cost challenges into relevant products materials with minimal loss efficiency. In this article, we present an ‘in situ’ (one-pot) process formation...

This work describes the design, fabrication and characterization of a paper-based microfluidic device for ultra-low detection urea through enzyme catalysis. The system comprises an entry port, fluidic channel, reaction zone two electrodes (contacts). Wax printing was used to create channels on surface chromatography paper. Pre-conceptualized designs channel are wax-printed paper substrate while screen-printed. printed with wax is heated cause reflow along thickness that selectively creates...

The wettability and evaporation of water–ethanol binary droplets on the substrate with micropyramid cavities are studied by controlling initial ethanol concentrations. form octagonal wetting areas substrate. As concentration increases, side ratio octagon increases from 1.5 at 0% to 3.5 30% concentration. increasing indicates that area transforms an a square if we consider be its four corners cut. experience pinning–depinning transition during evaporation. pure water sessile droplet...

The photocatalytic self-cleaning characteristics of titania facilitate the fabrication reuseable templates for protein nanopatterning. Titania nanostructures were fabricated over square centimeter areas by interferometric lithography (IL) and nanoimprint (NIL). With use a Lloyd's mirror two-beam interferometer, self-assembled monolayers alkylphosphonates adsorbed on native oxide Ti film patterned nanolithography. In regions exposed to maximum in interferogram, monolayer was removed...

Self-assembled monolayers (SAMs) of alkanethiols have been patterned on micrometre and nanometre length scales by exposure to light from a frequency doubled argon ion laser. Friction force microscopy shows that the patterning speed depends nature terminal group is in order COOH> CH3, reverse reported previously using mercury arc lamp, indicating different photo-oxidation mechanism responsible. It suggested this involves creation hot electrons at gold surface initiate oxidation adsorbate....

Using nanoimprint lithography, arrays of highly ordered patterns polyelectrolyte multilayer microcapsules consisting alternating layers poly(allylamine hydrochloride) and poly(sodium 4-styrene sulfonate) have been achieved. Anchoring the capsules on a pre-patterned substrate facilitates utilization their various capabilities in lab-on-a chip devices. In this paper we demonstrated very effective method to entrap soft into surface cavities. Supported were applied as depots for loading storage...

Directed self-assembly of nanoparticles (DSA-n) is an approach that creates suitable conditions to capture randomly dispersed in a liquid and position them into predefined locations on solid template. Although DSA-n emerging as potential bottom-up patterning technique build nanostructures using various sizes, geometries material compositions, there are still several outstanding challenges. In this paper, we focus the sub-10 nm particles topographical templates guide 1D 2D ordered arrays. The...

The advancement of molecular nanotechnology requires new tools for the characterization surface chemical reactivity with nanometer spatial resolution. While spectroscopy on sub-100 nm length scales remains challenging, friction force microscopy (FFM) is a promising tool materials, although to date it has been little used in studies reactivity. Here we report use FFM measure kinetics photo-oxidation self-assembled monolayers (SAMs) alkanethiols adsorbed gold surfaces. Two alternative...

Producing and maintaining specific liquid patterns during evaporation holds great potential for techniques of printing coating. Here we report the control over evolution surfactant solution droplets on micropyramid substrates evaporation. The polygonal droplet shape is achieved drying rather than solely at beginning. As initial concentration 0.04 mM, maintains its octagonal throughout lifetime. Interestingly, transforms into a square as reaches 0.8 mM. These findings can shed light wetting...

Molybdenum disulfide (MoS2) is traditionally grown at a high temperature and subsequently patterned to study its electronic properties or make devices. This method imposes severe limitations on the shape size of MoS2 crystals that can be precisely required positions. Here, we describe direct nanoscale patterning room by exposing molybdenum thiocubane single-source precursor beam electrons. thiocubanes with various alkylxanthate moieties [Mo4S4(ROCS2)6, where R = alkyl] were prepared using...

Abstract Understanding noncircular deposition patterns can offer broad applications; however, the phenomena have not been thoroughly studied. We experimentally investigate particle self‐assembly of microspherical polystyrene particle‐laden sessile droplets dried on a micropyramid cavity substrate. The sizes and concentrations in are found to modify inner with octagonal perimeter. mass 0.5% higher evaporate pinned contact lines. capillary flow flushes 3 µm particles line creates outer‐ring...

This article presents a scalable technique to precisely deposit and pattern graphitic oxide (GO) flakes onto SiO2/Si or glass substrate. A blanket coating of GO was first applied from colloidal solution an amine-functionalized The amine termination used enhance the adhesion sheets poly(methyl methacrylate) (PMMA) etch mask patterned via nanoimprint lithography on top coating. An oxygen plasma then remove areas unprotected by PMMA mask. dissolved solvent lift-off leaving behind lines. lines...

Abstract Micro‐structure patterned substrates attract our attention due to the special and programmable wettabilities. The interaction between liquid micro/nano structures gives rise controllable spreading thus evaporation. For exploration of application versatility, introduction nanoparticles in droplet results among particles, microstructures. In addition, temperature strongly affects contact line evaporative property. evaporation sessile droplets nanofluids on a micro‐grooved solid...

Wetting transitions induced by varying the components in a solution of drying droplet can lead to its evolving shape on textured surface. It provide new insights liquid pattern control through manipulating solutions. We show pronounced wetting for surfactant droplets micropyramid-patterned At low initial concentrations, maintains an octagonal until end drying. intermediate early octagon spreads square, which later evolves stretched rectangle. high mainly exhibits "octagon-to-square"...

Directed self-assembly of nanoparticles using topographical templates has demonstrated great capabilities ordering particles at their maximum packing fraction resulting from template confinement effects and free energy minimization. However, to self-assemble nanostructures a lower with precise control over particle's positioning is challenging due the high entropy such system. Here, by fabricating irregular cavities together appropriate choice solvent, we demonstrate 8 nm Au within...

Nanoimprint molds are traditionally made from silicon. Silicon suffer distinct disadvantages as they brittle, prone to damage, scratch easily, and can only be used in a planar format. This has limited their use higher throughput systems where flexible required such roll-to-roll roll-to-plate systems. Nickel (Ni) molds, which now de-rigueur both batch roller nanoimprint processes, address these problems, but fabrication durability issues limit availability effectiveness production. In this...

Nanoimprint lithography is traditionally thought of as a one-to-one pattern replication process, where the negative surface relief from mold reproduced exactly onto resist material. As such, each design will require to be fabricated with required. The used typically by various lithographic processes, many which are costly and time-consuming. In this work, we report use "mix match" sequential imprinting technique line-space patterns different gap sizes were achieved through combinations...

This work presents a procedure for large-area patterning of designed plasmon resonators that are much smaller than possible with conventional lithography techniques. Fused Colloidal Nanopatterning combines directed self-assembly and controlled fusing spherical colloidal nanoparticles. The two-step approach first patterns surface covered hydrogen silsesquioxane, an electron beam resist, forming traps into which the gold nanoparticles self-assemble. Second, patterned controllably fused to form...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Karen S. L. Chong, Yeong-Yuh Lee, Hong Yee Low; Recessed area patterning via nanoimprint lithography. J. Vac. Sci. Technol. B 1 November 2011; 29 (6): 060602. https://doi.org/10.1116/1.3660393 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar...