Large area patterning of ultra-high thermal-stable structural colors in transparent solids

Biomimetic structures such as structural colors demand a fabrication technology of complex three-dimensional nanostructures on large areas. Nanoimprint lithography (NIL) is capable of large area replication of three-dimensional structures, but the master stamp fabrication is often a bottleneck. We have demonstrated different approaches allowing for the generation of sophisticated undercut T-shaped masters for NIL replication. With a layer-stack of phase transition material (PTM) on poly-Si, we have demonstrated the successful fabrication of a single layer undercut T-shaped structure. With a multilayer-stack of silicon oxide on silicon, we have shown the successful fabrication of a multilayer undercut T-shaped structures. For patterning optical lithography, electron beam lithography and nanoimprint lithography have been compared and have yielded structures from 10 µm down to 300 nm. The multilayer undercut T-shaped structures closely resemble the geometry of the surface of a Morpho butterfly, and may be used in future to replicate structural colors on artificial surfaces.

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Solution route to large area all-TiO2 one-dimensional photonic crystals with high reflectivity and different structural colors

Nanotechnology ◽

10.1088/1361-6528/ab646f ◽

2020 ◽

Vol 31 (13) ◽

pp. 135209 ◽

Cited By ~ 1

Author(s):

Xin Hu ◽

Xiang Zhang ◽

Xinrui Chen ◽

Ming Luo

Keyword(s):

Photonic Crystals ◽

Large Area ◽

One Dimensional ◽

Structural Colors ◽

High Reflectivity ◽

Solution Route

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Synthesis of monodisperse single-crystal Cu2O spheres and their application in generating structural colors

Journal of Materials Chemistry C ◽

10.1039/c9tc00809h ◽

2019 ◽

Vol 7 (15) ◽

pp. 4551-4558 ◽

Cited By ~ 6

Author(s):

Jiajie Bi ◽

Suli Wu ◽

Hongbo Xia ◽

Lu Li ◽

Shufen Zhang

Keyword(s):

Single Crystal ◽

Room Temperature ◽

Building Blocks ◽

Large Area ◽

Structural Colors ◽

Photonic Structures ◽

Spray Method ◽

Solid Spheres

A two-step reductive strategy is developed to synthesize monodisperse single-crystal Cu2O solid spheres at room-temperature. The single-crystal spheres with adjustable diameter were used as building blocks to form amorphous photonic structures by spray method, which exhibits vivid colors. This may open a new way to realize large area film with vivid structure color.

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Large-Area Fabrication of Structurally Colored and Humidity Sensitive Composite Nanofilm via Ultrasonic Spray-Coating

Polymers ◽

10.3390/polym13213768 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3768

Author(s):

Sijun Li ◽

Donghui Kou ◽

Shufen Zhang ◽

Wei Ma

Keyword(s):

Raw Materials ◽

Composite Films ◽

Spray Coating ◽

Processing Parameters ◽

Water Vapor Adsorption ◽

Silicon Wafers ◽

Structural Color ◽

Large Area ◽

Structural Colors ◽

Ultrasonic Spray

Intelligent structural colors have received extensive attention in recent years due to their diverse applications. However, the large-area, uniform, and cost-effective fabrication of ultra-thin structural color films is still challenging. Here, for the first time, we design and employ an ultrasonic spray-coating technique with non-toxic, green nano-silica and polyvinylpyrrolidone as raw materials, to prepare structural color films on silicon wafers. Due to the addition of polyvinylpyrrolidone, the coffee-ring effect during droplet drying is suppressed and uniform composite films are formed. We further perform a detailed study of the influence of various processing parameters including silica/polyvinylpyrrolidone concentration, substrate temperature, nozzle-to-substrate distance, and number of spray-passes on film roughness and thickness. By increasing the number of spray-passes from 10 to 30, the film thickness from 120 to 340 nm is modulated, resulting in different colors, and large-area and uniform colors on commercial round silicon wafers with 15 cm diameter are achieved. The silica/polyvinylpyrrolidone composite films show strong hydrophilicity and are sensitive to humidity changes, leading to quickly tunable and reversible structural colors. Quartz crystal microbalance with dissipation demonstrates water vapor adsorption and condensation on the nanofilm when increasing environmental humidity. Thereby, ultrasonic spray-coating as a novel film fabrication technique provides a feasible scheme for large-area preparation of intelligent structural colors.

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Formation of laser-induced periodic surface nanometric concentric ring structures on silicon surfaces through single-spot irradiation with orthogonally polarized femtosecond laser double-pulse sequences

Nanophotonics ◽

10.1515/nanoph-2020-0568 ◽

2021 ◽

Vol 10 (2) ◽

pp. 1273-1283

Author(s):

Wei Liu ◽

Jie Hu ◽

Lan Jiang ◽

Ji Huang ◽

Jiangang Lu ◽

...

Keyword(s):

Femtosecond Laser ◽

Pulse Sequences ◽

Double Pulse ◽

Silicon Surfaces ◽

Large Area ◽

Concentric Ring ◽

Periodic Surface ◽

Single Spot ◽

Structural Colors ◽

Ring Structures

Abstract In this study, we report the formation of laser-induced periodic surface nanometric concentric ring structures on silicon surfaces through single-spot irradiation with orthogonally polarized femtosecond laser double-pulse sequences (OP pulses). The period of the ring structures is marginally smaller than the irradiated laser’s wavelength, which indicates that the structures are a type of low-spatial-frequency laser-induced periodic surface structures. Regular nanometric concentric ring structures can be formed when the time delay between two subpulses is approximately 1 ps (roughly from 500 fs to 1.5 ps) and the number of laser bursts is approximately 4. The formation mechanism of the concentric ring structures is attributed to the surface wave (i.e., cylindrical wave) stimulated by OP pulses through single-spot irradiation is radially distributed. Large area of concentric ring structures eliminating anisotropy in the generation of structural colors was shown in this paper.

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Synthesis of High-Performance Photonic Crystal Film for SERS Applications via Drop-Coating Method

Coatings ◽

10.3390/coatings10070679 ◽

2020 ◽

Vol 10 (7) ◽

pp. 679

Author(s):

Ming-Xue Wei ◽

Chao-Hui Liu ◽

Han Lee ◽

Bo-Wei Lee ◽

Chun-Han Hsu ◽

...

Keyword(s):

Particle Size ◽

Photonic Crystal ◽

Band Gap ◽

Colloidal Particles ◽

Laser Source ◽

Synthesis Process ◽

Large Area ◽

Structural Colors ◽

Crystal Film ◽

Coating Method

Silica nanospheres with a well-controlled particle size were prepared via a nucleation-to-growth synthesis process. A facile method is proposed for improving the self-assembly behavior of silica colloidal particles in droplet coatings by the simple controlling of the drying temperature. It is shown that a periodically arranged, opal-structured, photonic crystal film with a large area of approximately 4.0 cm2 can be prepared, even when the particle size is up to 840 nm. When the band gap of the silica photonic crystals falls in the visible-light region, the crystals exhibit distinct structural colors. Moreover, the wavelength of the reflected light increases with an increasing particle size of silica. When the photonic band gap overlaps the wavelength of the laser source, the overall Raman spectrum intensity is significantly enhanced. Accordingly, the proposed nucleation-to-growth process and drop-coating method provides a cheap and simple approach for the manufacture of uniform sized silica and surface-enhanced Raman scattering substrates, respectively.

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Electrodeposition of Large Area, Angle-Insensitive Multilayered Structural Colors

ACS Applied Materials & Interfaces ◽

10.1021/acsami.9b10236 ◽

2019 ◽

Vol 11 (32) ◽

pp. 29065-29071 ◽

Cited By ~ 4

Author(s):

Chengang Ji ◽

Saurabh Acharya ◽

Kaito Yamada ◽

Stephen Maldonado ◽

L. Jay Guo

Keyword(s):

Large Area ◽

Structural Colors

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Convergent Beam Electron Diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070072 ◽

1978 ◽

Vol 36 (3) ◽

pp. 304-315

Author(s):

G. Lehmpfuhl

Keyword(s):

Electron Diffraction ◽

Diffraction Pattern ◽

Crystal Surface ◽

Diffraction Spot ◽

Crystal Thickness ◽

Large Area ◽

Electron Microscopic ◽

Additional Information ◽

Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

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TEM Study of a Tilt Boundary in Hot-Pressed Silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097454 ◽

1981 ◽

Vol 39 ◽

pp. 160-161

Author(s):

C. B. Carter ◽

J. Rose ◽

D. G. Ast

Keyword(s):

Electron Diffraction ◽

Imaging Technique ◽

Interface Structure ◽

Large Area ◽

Weak Beam ◽

Lattice Fringe ◽

Electron Diffraction Technique ◽

Tilt Boundaries ◽

Beam Technique ◽

Twist Boundaries

The hot-pressing technique which has been successfully used to manufacture twist boundaries in silicon has now been used to form tilt boundaries in this material. In the present study, weak-beam imaging, lattice-fringe imaging and electron diffraction techniques have been combined to identify different features of the interface structure. The weak-beam technique gives an overall picture of the geometry of the boundary and in particular allows steps in the plane of the boundary which are normal to the dislocation lines to be identified. It also allows pockets of amorphous SiO2 remaining in the interface to be recognized. The lattice-fringe imaging technique allows the boundary plane parallel to the dislocation to be identified. Finally the electron diffraction technique allows the periodic structure of the boundary to be evaluated over a large area - this is particularly valuable when the dislocations are closely spaced - and can also provide information on the structural width of the interface.

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P20 phosphor on polyimide as a large area high-resolution transmission screen for slow scan CCD systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136477 ◽

1995 ◽

Vol 53 ◽

pp. 20-21

Author(s):

C. C. Ahn ◽

S. Karnes ◽

M. Lvovsky ◽

C. M. Garland ◽

H. A. Atwater ◽

...

Keyword(s):

Mechanical Stability ◽

High Energy ◽

Practical Implementation ◽

Line Pair ◽

Modulation Transfer ◽

Large Area ◽

Ccd Imaging ◽

Transmission Electron ◽

The One ◽

Beam Broadening

The bane of CCD imaging systems for transmission electron microscopy at intermediate and high voltages has been their relatively poor modulation transfer function (MTF), or line pair resolution. The problem originates primarily with the phosphor screen. On the one hand, screens should be thick so that as many incident electrons as possible are converted to photons, yielding a high detective quantum efficiency(DQE). The MTF diminishes as a function of scintillator thickness however, and to some extent as a function of fluorescence within the scintillator substrates. Fan has noted that the use of a thin layer of phosphor beneath a self supporting 2μ, thick Al substrate might provide the most appropriate compromise for high DQE and MTF in transmission electron microcscopes which operate at higher voltages. Monte Carlo simulations of high energy electron trajectories reveal that only little beam broadening occurs within this thickness of Al film. Consequently, the MTF is limited predominantly by broadening within the thin phosphor underlayer. There are difficulties however, in the practical implementation of this design, associated mostly with the mechanical stability of the Al support film.

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