25 nm-Feature, 10⁴-aspect-ratio, 10 mm²-area single-pulsed laser nanolithography

One of the major challenges in the rapidly advancing field of nanophotonics is creating high-aspect-ratio nanostructures over large-area with consistent precision. Traditional techniques like photolithography and etching fall short, being limited to fabricating structures with a typical feature size of 100 nm and a maximum aspect ratio of 30:1. To break through these barriers, herein we introduce a strategy, called wet-chemical etching assisted aberration-enhanced single-pulsed femtosecond laser-supplemented nanolithography (WEALTH), for manufacturing large-area deep holey nanostructures. This strategy enables fabrication of nanostructures with diameters as small as 25 nm (exceeding 1/30 of Abbe's diffraction limit), aspect ratios greater than 10⁴:1, and large-area holey lattices spanning 10 mm² with potential scalability up to several cm². We have successfully harnessed this technique to develop cutting-edge applications, including immunoassay biosensing chips, large-area nanophotonic crystals, nanophotonic crystal microcavities, and chiral nanophotonic devices. Moreover, it is adaptable to a wide range of materials, including crystals, glasses, and silicon-based semiconductors. Our approach offers high flexibility in customizing large-area holey nanophotonic structures, paving the way for breakthrough advancements in 3D integrated optics.