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Abstract A cantilever‐free scanning probe lithography (CF‐SPL)‐based method for the rapid polymerization of nanoscale features on a surface via crosslinking and thiol‐acrylate photoreactions is described, wherein the nanoscale position, height, and diameter of each feature can be finely and independently tuned. With precise spatiotemporal control over the illumination pattern, beam pen lithography (BPL) allows for the photo‐crosslinking of polymers into ultrahigh resolution features over centimeter‐scale areas using massively parallel >160 000 pen arrays of individually addressable pens that guide and focus light onto the surface with sub‐diffraction resolution. The photoinduced crosslinking reaction of the ink material, which is composed of photoinitiator, diphenyl(2,4,6‐trimethylbenzoyl) phosphine oxide, poly(ethylene glycol) diacrylate, and thiol‐modified functional binding molecules (i.e., thiol‐PEG‐biotin or 16‐mercaptohexanoic acid), proceeds to ≈80% conversion with UV exposure (72 mW cm−2) for short time periods (0.5 s). Such polymer patterns are further reacted with proteins (streptavidin and fibronectin) to yield protein arrays with feature arrangements at high resolution and densities controlled by local UV exposure. This platform, which combines polymer photochemistry and massive arrays of scanning probes, constitutes a new approach to making biomolecular microarrays in a high‐throughput and high‐yielding manner, opening new routes for biochip synthesis, bioscreening, and cell biology research.
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Roll‐to‐Roll Compatible Topochemical Wetting Control for Metamaterial Printing
Abstract The widespread utilization of metamaterials, despite their immense transformative potential, faces challenges regarding scalability in mass production. To address these limitations, an additive method that leverages liquid inks and selective wetting to produce scalable and cost‐effective metamaterials is presented. UV‐based imprinting lithography is utilized to fabricate surface energy‐modulated patterns, enabling precise solution patterning. This approach, unlike conventional UV‐based imprinting lithography, not only accurately produces the negative replica of the stamp topography during UV‐induced crosslinking but also transfers a hydrophobic layer onto the raised surfaces of the imprinted hydrophilic layer, resulting in 3D shapes with spatially modulated surface energy. In the second process step, a functional ink is dragged over the patterned substrate where it dewets to fill the hydrophilic recesses. This innovative process enables high‐speed metamaterial production, with ink deposition speeds up to 12 m min−1. The method accommodates a wide range of inks, including metals, dielectrics, and semiconductors, providing meticulous control over vertical structures such as pattern thickness and hetero‐multilayer formation. Additionally, it offers flexibility in creating metamaterials on free‐standing ultra‐thin sheets, introducing desirable attributes like foldability and disposability. The effectiveness of this approach is validated through the fabrication and characterization of metallic metamaterials.
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- Award ID(s):
- 2011401
- PAR ID:
- 10506822
- Publisher / Repository:
- Advanced Optical Materials
- Date Published:
- Journal Name:
- Advanced Optical Materials
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/adom.202302785
