Sub-wavelength lithography of complex 2D and 3D nanostructures without two-photon dyes

Chaudhary, Raghvendra Pratap; Jaiswal, Arun; Ummethala, Govind; Hawal, Suyog R; Saxena, Sumit; Shukla, Shobha

doi:10.1016/j.addma.2017.05.003

Cited by 11 publications

(7 citation statements)

References 39 publications

(31 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among the top technological achievements of the last century in nanofabrication, photon-assisted processing methods are with no doubt the more technologically advanced ones. Photolithography combined with dry or wet etching of the hard metal oxides is today available with acceptable performances in terms of quality, versatility, resolution, throughput, cost, and achievable morphologies. − Still, these methods remain cumbersome and are constrained by a limited choice of required photosensitive selective masks, containing complex organic radicals or cationic nonlinear absorbers (photoinitiators) which are expensive, often colored, poorly soluble in photopolymers, and could be toxic . Furthermore, photolithography faces an intrinsic critical limitation in resolution dictated by the wavelength of incident writing light waves (high-energy ultraviolet radiation (deep-UV) is used nowadays in production lines to elaborate features smaller than 40 nm).…”

Section: Generalities On Nanofabrication Techniques and Nilmentioning

confidence: 99%

“…8−11 Still, these methods remain cumbersome and are constrained by a limited choice of required photosensitive selective masks, containing complex organic radicals or cationic nonlinear absorbers (photoinitiators) which are expensive, often colored, poorly soluble in photopolymers, and could be toxic. 12 Furthermore, photolithography faces an intrinsic critical limitation in resolution dictated by the wavelength of incident writing light waves (high-energy ultraviolet radiation (deep-UV) is used nowadays in production lines to elaborate features smaller than 40 nm 13 ). Besides, these methods require hard-masks that need to be prepared by cumbersome electron beam lithography (EBL) or focused ions beam (FIB).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Nanoimprint Lithography Processing of Inorganic-Based Materials

et al. 2021

View full text Add to dashboard Cite

We review past and recent progress in Nano-Imprint Lithography (NIL) methods to (nano-) structure inorganic materials from sol-gel liquid formulations and colloidal suspensions onto a surface. This technique, first inspired by embossing techniques, was developed for soft polymer processing, as final or intermediate materials, but is today fully adapted to hard inorganic materials with high dielectric constant, such as metal oxides, with countless chemical compositions provided by the sol-gel chemistry. Consequently, NIL has become a versatile, high throughput, and highly precise microfabrication method that is mature for lab developments and scaling up. We first describe the state-of-the-art in nanofabrication methods and the plethora of approaches developed in the last decades to imprint metal oxides from inorganic solutions. These are discussed and compared in terms of performances, issues, and ease of implementation. The final part is devoted to relevant applications in domains of interest. Generalities on Nano fabrication techniques and NILFrom the early ages, technics to cut, sculpt, etch, mold, assemble pieces of matter have been developed and constantly optimized to satisfy the growing demand for functional materials. Since the inception of nanotechnology, these operations have to be mastered at the nanoscale. For these tasks, many top-down and bottom-up methods exist. However, they do not simultaneously fulfill all the necessary criteria of performance such as spatial resolution, pattern complexity, hierarchy, scalability, dimensionality, costeffectiveness, a span of processable materials. Thus, motivations to optimize them and develop new ones persist as a flourishing domain of research and development.Many materials exhibiting various intrinsic properties (mechanical, chemical, electrical, optical, thermal, etc.) are exploited in numberless functions once nanostructured onto a surface. Amongst them, metal oxides are extremely valuable for their extreme chemical, mechanical and thermal stability and range of physicalchemical properties. Thanks to its hardness, chemical inertness, transparency and low background fluorescence, glass is one of the preferred choices for micro-and nano-fluidics device fabrication. In photonics, metasurfaces require optical properties that are found in dielectrics such as SiO2 often combined with high index dielectric TiO2 or (plasmonic) gold 1 . For nano-electronics, silica remains one of the key

show abstract

Section: Generalities On Nanofabrication Techniques and Nilmentioning

confidence: 99%

mentioning

confidence: 99%

Nanoimprint Lithography Processing of Inorganic-Based Materials

et al. 2021

View full text Add to dashboard Cite

show abstract

“…In order to achieve sub-wavelength-scale direct writing without using dye molecules, a highly efficient photoinitiator can be applied to produce free radicals quickly and sensitively in small areas at low optical doses [118]. Chaudhary et al have investigated the polymer material, Ethyl-2,4,6-Trimethyl-benzoylphenylphosphinate (Lucirin-TPO-L), as the high-dose two-photon photoinitiator additive to replace dye molecules, which is inexpensive and readily soluble in polymers [119]. Although its two-photon absorption coefficient is small, it has a high free radical quantum yield of 0.99 [120].…”

Section: Special Materials For Dlwmentioning

confidence: 99%

Polymer-Based Device Fabrication and Applications Using Direct Laser Writing Technology

Yin

et al. 2019

Polymers

View full text Add to dashboard Cite

Polymer materials exhibit unique properties in the fabrication of optical waveguide devices, electromagnetic devices, and bio-devices. Direct laser writing (DLW) technology is widely used for micro-structure fabrication due to its high processing precision, low cost, and no need for mask exposure. This paper reviews the latest research progresses of polymer-based micro/nano-devices fabricated using the DLW technique as well as their applications. In order to realize various device structures and functions, different manufacture parameters of DLW systems are adopted, which are also investigated in this work. The flexible use of the DLW process in various polymer-based microstructures, including optical, electronic, magnetic, and biomedical devices are reviewed together with their applications. In addition, polymer materials which are developed with unique properties for the use of DLW technology are also discussed.

show abstract

“…Two-photon curable resins typically incorporate photoinitiators/photosensitizers that can be photoactivated using ultraviolet (UV) radiation. They however result in reduced resolutions due to their low two-photon absorption cross-section (σ) values. − To unleash the true potential of TPL, a few attempts have been made toward the development of two-photon chromophore/fluorophore materials with large two-photon absorption cross-section (σ) values. Structure–property relationships have been explored extensively to attain molecules with optimal σ values. − Several groups have theoretically studied and/or synthesized molecules consisting of dipolar, quadrupolar, and octupolar moieties attached to a common core to obtain linear/multibranched, symmetrical/asymmetrical molecules. ,− Electron donor/acceptor (D/A) moieties attached to hetereocyclic/aromatic/oleofinic motifs to serve as π and/or semi rigid (Sπ) polarizable electron bridges have been reported to enhance σ considerably.…”

Section: Introductionmentioning

confidence: 99%

Additive-Free All-Carbon Composite: A Two-Photon Material System for Nanopatterning of Fluorescent Sub-Wavelength Structures

et al. 2021

Self Cite

View full text Add to dashboard Cite

The major bottleneck in fabrication of engineered 3D nanostructures is the choice of materials. Adding functionality to these nanostructures is a daunting task. In order to mitigate these issues, we report a two-photon patternable all carbon material system which can be used to fabricate fluorescent 3D micro/nanostructures using two-photon lithography, with subwavelength resolution. The synthesized material system eliminates the need to use conventional two-photon absorbing materials such as two-photon dyes or two-photon initiators. We have used two different trifunctional acrylate monomers and carbon dots, synthesized hydrothermally from a polyphenolic precursor, to formulate a two-photon processable resin. Upon two-photon excitation, photogenerated electrons in the excited states of the carbon dots facilitate the free radical formation at the surface of the carbon dots. These radicals, upon interaction with vinyl moieties, enable cross-linking of acrylate monomers. Free-radical induced two-photon polymerization of acrylate monomers without any conventional proprietary two-photon absorbing materials was accomplished at an ultrafine subwavelength resolution of 250 nm using 800 nm laser excitation. The effect of critical parameters such as average laser power, carbon dot concentration, and radiation exposure were determined for the fabrication of one-, two-, and three-dimensional functional nanostructures, applicable in a range of domains where fluorescence and toxicity are of the utmost importance. A fabrication speed as high as 100 mm/s was achieved. The ability to fabricate functional 3D micro-/nanostructures is anticipated to instigate a paradigm shift in various areas such as metamaterials, energy storage, drug delivery, and optoelectronics to name a few.

show abstract

Sub-wavelength lithography of complex 2D and 3D nanostructures without two-photon dyes

Cited by 11 publications

References 39 publications

Nanoimprint Lithography Processing of Inorganic-Based Materials

Nanoimprint Lithography Processing of Inorganic-Based Materials

Polymer-Based Device Fabrication and Applications Using Direct Laser Writing Technology

Additive-Free All-Carbon Composite: A Two-Photon Material System for Nanopatterning of Fluorescent Sub-Wavelength Structures

Contact Info

Product

Resources

About