Nanopatterning with UV Optical Lithography

AbstractOptical lithography at ultraviolet (UV) wavelengths is the standard process for patterning 90-nm state-of-the-art devices in the semiconductor industry, and extensions to 45 nm and below are currently being explored. With such high resolution, the inherent high throughput of optical lithography will enable the development of a broad range of applications beyond semiconductor electronics. In this article, we will review progress toward nanopatterning with UV light in a variety of materials and geometries.The common thread is the use of short wavelengths, 193 nm or 157 nm, coupled with immersion to further reduce the effective wavelength. Densely spaced, 32-nm (and even smaller) features have been patterned, facilitating the future preparation of large-area, deeply scaled microelectronics, nanophotonics, nanobiology, and molecular-scale self-assembly.

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Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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IMG2nDSM: Height Estimation from Single Airborne RGB Images with Deep Learning

Remote Sensing ◽

10.3390/rs13122417 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2417

Author(s):

Savvas Karatsiolis ◽

Andreas Kamilaris ◽

Ian Cole

Keyword(s):

Deep Learning ◽

State Of The Art ◽

Aerial Imagery ◽

Aerial Images ◽

Surface Model ◽

Large Area ◽

Digital Terrain ◽

Terrain Models ◽

Architectural Features ◽

Rgb Images

Estimating the height of buildings and vegetation in single aerial images is a challenging problem. A task-focused Deep Learning (DL) model that combines architectural features from successful DL models (U-NET and Residual Networks) and learns the mapping from a single aerial imagery to a normalized Digital Surface Model (nDSM) was proposed. The model was trained on aerial images whose corresponding DSM and Digital Terrain Models (DTM) were available and was then used to infer the nDSM of images with no elevation information. The model was evaluated with a dataset covering a large area of Manchester, UK, as well as the 2018 IEEE GRSS Data Fusion Contest LiDAR dataset. The results suggest that the proposed DL architecture is suitable for the task and surpasses other state-of-the-art DL approaches by a large margin.

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Self-Assembly Technique Enables Fabrication of Large-Area, Periodic Arrays of Aligned Carbon Nanotubes

MRS Bulletin ◽

10.1557/mrs2003.27 ◽

2003 ◽

Vol 28 (2) ◽

pp. 94-95

Author(s):

Steven Trohalaki

Keyword(s):

Carbon Nanotubes ◽

Self Assembly ◽

Large Area ◽

Periodic Arrays ◽

Aligned Carbon Nanotubes ◽

Assembly Technique

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Self-Assembly of Monolayers of Submicron Sized Particles on Thin Liquid Films

Volume 7A: Fluids Engineering Systems and Technologies ◽

10.1115/imece2013-65324 ◽

2013 ◽

Author(s):

Shriram Pillapakkam ◽

N. A. Musunuri ◽

P. Singh

Keyword(s):

Electric Field ◽

Self Assembly ◽

Uv Light ◽

Capillary Forces ◽

Liquid Films ◽

Thin Liquid Films ◽

Liquid Interfaces ◽

Uv Curable ◽

Particle Monolayer ◽

Uv Curable Resin

In this paper, we present a technique for freezing monolayers of micron and sub-micron sized particles onto the surface of a flexible thin film after the self-assembly of a particle monolayer on fluid-liquid interfaces has been improved by the process we have developed where an electric field is applied in the direction normal to the interface. Particles smaller than about 10 microns do not self-assemble under the action of lateral capillary forces alone since capillary forces amongst them are small compared to Brownian forces. We have overcome this problem by applying an electric field in the direction normal to the interface which gives rise to dipoledipole and capillary forces which cause the particles to arrange in a triangular pattern. The technique involves assembling the monolayer on the interface between a UV-curable resin and another liquid by applying an electric field, and then curing the resin by applying UV light. The monolayer becomes embedded on the surface of the solidified resin film.

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Towards achieving a large-area and defect-free nano-line pattern via controlled self-assembly by sequential annealing

Giant ◽

10.1016/j.giant.2021.100078 ◽

2021 ◽

pp. 100078

Author(s):

Tao Wen ◽

Bo Ni ◽

Yuchu Liu ◽

Wei Zhang ◽

Zi-Hao Guo ◽

...

Keyword(s):

Self Assembly ◽

Line Pattern ◽

Large Area

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Engineering the shape of Zinc Oxide crystals via sonochemical or hydrothermal solution-based methods

MRS Proceedings ◽

10.1557/proc-1087-v06-04 ◽

2008 ◽

Vol 1087 ◽

Author(s):

Marco Palumbo ◽

Simon J. Henley ◽

Thierry Lutz ◽

Vlad Stolojan ◽

David Cox ◽

...

Keyword(s):

Zinc Oxide ◽

Self Assembly ◽

Hydrothermal Solution ◽

Good Control ◽

Transparent Conductors ◽

Zno Nanostructures ◽

Large Area ◽

Light Emitting Devices ◽

Wide Range ◽

Solution Methods

AbstractRecent results in the use of Zinc Oxide (ZnO) nano/submicron crystals in fields as diverse as sensors, UV lasers, solar cells, piezoelectric nanogenerators and light emitting devices have reinvigorated the interest of the scientific community in this material. To fully exploit the wide range of properties offered by ZnO, a good understanding of the crystal growth mechanism and related defects chemistry is necessary. However, a full picture of the interrelation between defects, processing and properties has not yet been completed, especially for the ZnO nanostructures that are now being synthesized. Furthermore, achieving good control in the shape of the crystal is also a very desirable feature based on the strong correlation there is between shape and properties in nanoscale materials. In this paper, the synthesis of ZnO nanostructures via two alternative aqueous solution methods - sonochemical and hydrothermal - will be presented, together with the influence that the addition of citric anions or variations in the concentration of the initial reactants have on the ZnO crystals shape. Foreseen applications might be in the field of sensors, transparent conductors and large area electronics possibly via ink-jet printing techniques or self-assembly methods.

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Large-area monolithic photonic crystal mirrors with high reflectivity in the 1250–1650nm band patterned by optical lithography

2008 IEEE/LEOS International Conference on Optical MEMs and Nanophotonics ◽

10.1109/omems.2008.4607841 ◽

2008 ◽

Cited By ~ 1

Author(s):

Il Woong Jung ◽

Shrestha Basu Mallick ◽

Olav Solgaard

Keyword(s):

Photonic Crystal ◽

Optical Lithography ◽

Large Area ◽

High Reflectivity

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Hydrogen Electrocatalysis: Self‐Assembly of Large‐Area 2D Polycrystalline Transition Metal Carbides for Hydrogen Electrocatalysis (Adv. Mater. 50/2018)

Advanced Materials ◽

10.1002/adma.201870385 ◽

2018 ◽

Vol 30 (50) ◽

pp. 1870385 ◽

Cited By ~ 1

Author(s):

Xining Zang ◽

Wenshu Chen ◽

Xiaolong Zou ◽

J. Nathan Hohman ◽

Lujie Yang ◽

...

Keyword(s):

Transition Metal ◽

Self Assembly ◽

Metal Carbides ◽

Large Area ◽

Transition Metal Carbides

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Electron Microscopy Study of Submicron Size Antiferromagnetic KMnF3 Nanoparticles and Their Self-assembly

MRS Proceedings ◽

10.1557/proc-775-p9.4 ◽

2003 ◽

Vol 775 ◽

Author(s):

Jeffrey Anderson ◽

Rubi Garcia ◽

Weilie L. Zhou

Keyword(s):

Electron Microscopy ◽

Self Assembly ◽

Room Temperature ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Submicron Particles ◽

Spherical Particles ◽

Large Area ◽

Homogeneous Crystal ◽

Field Emission Electron Microscopy

AbstractSubmicron KMnF3 cubic and spherical nanoparticles were synthesized using the reverse micelle method. The nanostructures of the nanocrystals were studied by field emission electron microscopy and transmission electron microscopy. KMnF3 nanocrystals synthesized at room temperature started with cubic submicron particles (∼100 nm) and consisted of KMnF3 nanocrystallites (10-15 nm). As the reaction continued, the nanocrystals fused together and transformed into perfect cubic nanocrystals. Spherical beads composed of KMnF3 nanocrystallites were observed at low temperature synthesis. As the reaction continued, the spherical particles grew larger, however, no characteristic cubic shape of KMnF3 nanoparticles were observed. Even as they grew larger, there was no evidence of homogeneous crystal morphology as seen in the room temperature samples. Cubic shape KMnF3 nanocrystals were self-assembled into large area self-assembling patterns.

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PhotoATRP Induced Self-Assembly (PhotoATR-PISA) Enables Simplified Synthesis of Responsive Polymer Nanoparticles in One-Pot

10.26434/chemrxiv.12988559 ◽

2020 ◽

Author(s):

Ali Shahrokhinia ◽

Randall Scanga ◽

Priyanka Biswas ◽

James Reuther

Keyword(s):

Self Assembly ◽

Glycidyl Methacrylate ◽

Uv Light ◽

Copper Catalyst ◽

Crosslinking Agent ◽

Polymer Nanoparticles ◽

One Pot ◽

Responsive Polymer ◽

Catalyst Systems ◽

First Time

ABSTRACT: Photo-controlled atom transfer radical polymerization (PhotoATRP) was implemented, for the first time, to accomplish polymerization induced self-assembly (PISA) mediated by UV light (λ = 365 nm) using ppm levels (ca. < 20 ppm) of copper catalyst at ambient temperature. Using CuIIBr2/tris(pyridin-2-ylmethyl)amine (TPMA) catalyst systems, PISA was per-formed all in one-pot starting from synthesis of solvophilic poly(oligo(ethylene oxide) methyl ether methacrylate) (POEGMA) blocks to core-crosslinked nanoparticles (NPs) utilizing poly(glycidyl methacrylate) (PGMA) and N,N-cystamine bismethacrylamide (CBMA) as the solvophobic copolymer and crosslinking agent, respectively. Sequential chain-extensions were performed for PGMA demonstrating capabilities for accessing multi-block copolymers with temporal control via switching the UV light on and off. Further, core-crosslinking of PISA nanoparticles was performed via the slow incorporation of the CBMA enabling one-pot crosslinking during the PISA process. Finally, the disulfide installed in the CBMA core-crosslinks allowed for the stimuli-triggered dissociation of nanoparticles using DL-dithiothreitol at acidic pH.

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