Maskless Plasmonic Lithography at 22 nm Resolution

Abstract

Optical imaging and photolithography promise broad applications in nano-electronics, metrologies, and single-molecule biology. Light diffraction however sets a fundamental limit on optical resolution, and it poses a critical challenge to the down-scaling of nano-scale manufacturing. Surface plasmons have been used to circumvent the diffraction limit as they have shorter wavelengths. However, this approach has a trade-off between resolution and energy efficiency that arises from the substantial momentum mismatch. Here we report a novel multi-stage scheme that is capable of efficiently compressing the optical energy at deep sub-wavelength scales through the progressive coupling of propagating surface plasmons (PSPs) and localized surface plasmons (LSPs). Combining this with airbearing surface technology, we demonstrate a plasmonic lithography with 22 nm half-pitch resolution at scanning speeds up to 10 m/s. This low-cost scheme has the potential of higher throughput than current photolithography, and it opens a new approach towards the next generation semiconductor manufacturing.

Plasmonic metalens for nanofabrication

“…1), consistent with the pioneering prediction given in 2004 [3] and comparable to the plasmonic maskless lithography [6,7]. It has also been shown that the resolution capability can be pushed down to 16 nm for gratings and 9 nm for isolated patterns through the self-aligned multiplepatterning technique [8], thus providing a viable alternative to traditional costly and complex optical lithography systems [9].…”

Three-dimensional deep sub-diffraction optical beam lithography with 9 nm feature size

“…1a). Though the use of near-field nano-focusing has recently enabled low-cost plasmonic lithography with sub-100 nm resolution and 22 nm feature size 2 , this approach inherently cannot facilitate the nanofabrication of three-dimensional (3D) structures that are highly required in next-generation nanophotonic devices 3,4 . Optical beam lithography (OBL) based on focusing through a high numerical aperture objective 5 is an ultimate approach to 3D nanofabrication (Fig.…”

Finite-Boundary Bowtie Aperture Antenna for Trapping Nanoparticles

“…Optical antennas have been widely employed as nanosources for higher harmonic light [4,5], thermal emitters [6], plasmonic sensors [7,8], and in applications such as photodetection or spontaneous emission efficiency enhancement [9,10], optical trapping, stacking and sorting [11], and subwavelength field confinement [12].…”