Inkjet printing is rapidly emerging as a means to fabricate low‐cost electronic devices; however, its widespread adoption is hindered by the complexity of the inks and the relatively high processing temperatures, limiting it to only a few metals and substrates. A new approach for inkjet printing is described, based on commercially available, particle‐free inks formulated from inorganic metal salts and their subsequent low‐temperature conversion to metallic structures by a non‐equilibrium, inert gas plasma. This single, general method is demonstrated for a library of metals including gold (Au), silver (Ag), copper (Cu), palladium (Pd), platinum (Pt), lead (Pb), bismuth (Bi), and tin (Sn). As one figure of merit, the resistivities of the printed metals are measured to be between 2× and 10× of the respective bulk metals. Uniquely, it is found that the printed metal films exhibit a very large surface area because of the plasma‐initiated nucleation and growth process, making this technique attractive for sensing device applications. A Bi‐based trace Pb sensor, an Au‐based amyloid‐β42sensor, and an Au‐based strain gauge are fabricated as representative chemical, biological, and mechanical sensors, and are found to exhibit enhanced sensitivity compared to analogues made with conventional methods.
This work presents a low‐cost, large‐scale nanofabrication approach that combines imprint lithography and silver doping (IL‐SD) to pattern chalcogenide glass (ChG) films for realizing IR devices. The IL‐SD method involves controled photodoping of silver (Ag) atoms into ChG films and selective removing of undoped ChG. For photodoping of Ag, an Ag‐coated elastomer stamp is brought in contact with the ChG film and exposed to ultraviolet light, and subsequently, the Ag atoms are photo‐dissolved into the ChG film following the nanopatterns on the elastomer stamp. Due to the high wet‐etching selectivity of the undoped ChG to Ag‐doped one, the ChG film can be precisely patterned with a spatial resolution on the order of a few tens of nanometers. Also, by controling the lateral diffusion of Ag atoms during ultraviolet exposure, it is possible to adjust the size of the final patterns formed in the ChG film. As an application demonstration of the IL‐SD process, the As2S3‐based near‐infrared photonic crystals (PhCs) in the wavelength range and flexible midinfrared PhCs are formed, and their optical resonances are investigated. The IL‐SD process enables the low‐cost fabrication of ChG nanostructures on different substrate materials and gives a great promise to realize various IR devices.
more » « less- Award ID(s):
- 1711839
- NSF-PAR ID:
- 10456275
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 16
- Issue:
- 19
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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