Patterning process development for NIL templates

Nano-imprint lithography (NIL) is expected as one of the candidates for 32nm node and below, because of its potential low lithography cost. NIL needs masks, which are referred as templates, have 1X patterns and therefore require significantly finer process capability than those for today's 4X masks. A transit from 4X to 1X means a big and hard technology jump and the NIL template would be a technology driver for the coming nodes, in terms of patterning process development. In this paper, among the important factors dominating the resolution of the mask making process, we focused particularly on the resist and the dry etch. We found that with tools used in the commercial mask shops today, and with modification of widely used resists, we could achieve 30nm isolated spaces and 50nm dense lines and holes. Quartz etching process was also optimized and we found that the etch process itself won't be the showstopper in this range of resolution.