Wafer-scale subwavelength excimer lithography enabled by dry-transferable photoresist

Abstract The rapid development of micro- and nanoscale devices has driven demand for wafer-scale, high-resolution nanostructure fabrication, which remains challenging for current nanolithography technologies. Here, we develop a cost-effective and high-throughput lithographic strategy for patterning sub-wavelength nanostructures over wafer-scale areas. This strategy is based on perfect conformal contact lithography combined with vacuum ultraviolet excimer irradiation at 172 nm. Using specially modified, transferable polymethyl methacrylate as a photoresist, the resulting approach enables high-fidelity, wafer-scale (8 inch) replication and fabrication of nanoscale (100 nm) patterns on both rigid and flexible substrates. We further develop a physical pattern-transfer method enabling high-resolution, solvent-free lift-off over large areas with 100% yield. The applicability of the lithography and pattern transfer strategy is demonstrated by the fabrication of 6560 nano-gap electrode structures over an area of 4 cm2 for MoS₂ transistor fabrication. Together with the demonstration of 12 representative transistors exhibiting on/off ratios approximately 108 and a large-aperture (10 cm) metalens enabling high-quality long-distance imaging, these results confirm the applicability of the proposed lithography and pattern transfer strategy across both electronic and optical devices.