Nanoimprinting has been applied in many micro- and nanoscale engineered devices; applications include displays, organic electronics, photovoltaics, optical films, and optoelectronics; and in some cases, direct imprinting of functional polymeric devices. Applications in the photonics area can significantly relieve the stringent requirement needed for nanoelectronics. We provide examples of structural colors and optical meta-surfaces facilitated by nanoimprinting, as well as plasmonic lithography masks that can produce deep-subwavelength structures using ordinary UV light.
Inkjet printing has been widely used in many applications, but still faces challenges in pattern precision and feature variations. Combining Nanoimprint for patterning and inkjet printing for material deposition will take the advantage of what both technologies can offer, and can provide a high precision additive manufacturing process. We will show printed photonic devices, e.g. electro-optic polymer based optical modulators.
To extend nanoimprinting to solid materials other than polymeric films will require innovative and non-conventional approaches. One such process is Metal-assisted chemical (Mac) imprint, which combines MacEtch and nanoiprint and enables direct MacEtch of Si substrate using a hybrid imprinting mold having noble metal mask. However, only low aspect ratio structures have been obtained because of the mass-transport limitation in the previous molds. Recently we effectively solved this problem by a using a specially made mold of Pt-coated anodized aluminum oxide (AAO) membrane, where the holes through the entire thickness drastically enhances the mass-transport. As a result, very high aspect ratio Si nanowires were achieved by MacImprint.
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Curvature-Adjustable Polymeric Nanolens Fabrication Using UV-Controlled Nanoimprint Lithography
Nanolenses are gaining importance in nanotechnology, but their challenging fabrication is thwarting their wider adoption. Of particular challenge is facile control of the lens’ curvature. In this work, we demonstrate a new nanoimprinting technique capable of realizing polymeric nanolenses in which the nanolens’ curvature is optically controlled by the ultraviolet (UV) dose at the pre-curing step. Our results reveal a regime in which the nanolens’ height changes linearly with the UV dose. Computational modeling further uncovers that the polymer undergoes highly nonlinear dynamics during the UV-controlled nanoimprinting process. Both the technique and the process model will greatly advance nanoscale science and manufacturing technology.
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- Award ID(s):
- 2129796
- NSF-PAR ID:
- 10438813
- Date Published:
- Journal Name:
- Micromachines
- Volume:
- 13
- Issue:
- 12
- ISSN:
- 2072-666X
- Page Range / eLocation ID:
- 2183
- 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/10.3390/mi13122183
