UV laser-assisted multiple evanescent waves lithography for near-field nanopatterning

A single exposure multiple evanescent waves interference lithography approach for patterning of nanoscale two-dimensional (2D) features is described and illustrated theoretically and experimentally in this Letter. Sub-70 nm (?? 0.19 ) full-width at half-maximum (FWHM) 2D features, with a pitch size smaller than ??/2, are fabricated by exposing conventional positive tone UV photoresist to the interference between four counter-propagating evanescent waves, which are generated by total internal reflection of polarised incident beams. The effects of polarisation and exposure duration are also investigated.