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We developed dielectric heating-assisted nanoimprint method for rapid fabrication of ultraflexible nanostructures. Using spin-coating polyvinyl-chloride (PVC) film on the glass slide, the dielectric heating on PVC film helped the pattern transfer from the mold to PVC film in few seconds. Various kinds of nanostructures were successfully made on PVC films with about 20-μm thickness. We demonstrated the applications of ultraflexible metallic nanostructures for bending measurement using surface plasmon resonance (SPR) and surface enhanced Raman scattering (SERS) on the curved surfaces. For measuring bending angles using SPR on capped nanowire arrays, the minimum detection angle was 2.4 × 10−3 degree under 0.02 nm wavelength resolution. For SERS measurement, the nanorod arrays on a curved substrate can increase SERS signals for two times as compared to planar SERS substrate.

We propose two approaches—hot-embossing and dielectric-heating nanoimprinting methods—for low-cost and rapid fabrication of periodic nanostructures. Each nanofabrication process for the imprinted plastic nanostructures is completed within several seconds without the use of release agents and epoxy. Low-cost, large-area, and highly sensitive aluminum nanostructures on A4 size plastic films are fabricated by evaporating aluminum film on hot-embossing nanostructures. The narrowest bandwidth of the Fano resonance is only 2.7 nm in the visible light region. The periodic aluminum nanostructure achieves a figure of merit of 150, and an intensity sensitivity of 29,345%/RIU (refractive index unit). The rapid fabrication is also achieved by using radio-frequency (RF) sensitive plastic films and a commercial RF welding machine. The dielectric-heating, using RF power, takes advantage of the rapid heating/cooling process and lower electric power consumption. The fabricated capped aluminum nanoslit array has a 5 nm Fano linewidth and 490.46 nm/RIU wavelength sensitivity. The biosensing capabilities of the metallic nanostructures are further verified by measuring antigen–antibody interactions using bovine serum albumin (BSA) and anti-BSA. These rapid and high-throughput fabrication methods can benefit low-cost, highly sensitive biosensors and other sensing applications.

We present radio-frequency (RF) heating-assisted nanoimprint lithography (NIL) for the rapid fabrication of nanostructured biochips. The chips were spin-coated using a RF-sensitive polymer film, namely polyethylene terephthalate glycol-modified (PETG). The RF heating process takes advantage of rapid temperature increases and cooling for NIL. Using a patterned nickel film as the mold, various nanostructures, such as nanowire, nanorod, and nanogrid arrays, were successfully fabricated within several seconds. For surface plasmon biosensing chips, the silver-coated nanowire arrays achieved a linewidth of 6.01 nm and wavelength sensitivity of 550 nm per refractive index unit. The functionality of the sensor was verified by observing the label-free antigen–antibody interactions.