Figure 5

SEM images of resist patterns for 60-nm half-pitch dense lines with variable air distances of 0, 40 and 80 nm.
(a–c) in the top row are for the near-field lithography under NI; (d–f) in the middle row and (g–i) in the bottom row represent the plasmonic cavity lens lithography under NI and high spatial frequency spectrum OAI, respectively.