The Effect of the Ratio of Lines to Spaces for Nanolithography Using Surface Plasmons

The effect of the ratio lines to spaces for nanolithography using surface plasmons was numerically investigated. The electric field distributions of the photoresist layer, at the top contact between the mask and the photoresist, and the bottom contact between the photoresist and the substrate, were determined in accordance with the ratio of the line to the space and the contrast of each case was calculated. Although all cases showed sub-60-nm feature size of less than lambda/7, the intensity and its effect on the nanolithography could be different depending on the ratio of lines to spaces. Therefore, an optimum point for nanolithography can exist, allowing simultaneous achievement of both high contrast and long propagation length.