A method for fabricating below 22nm feature patterns in quartz mold

摘要

In nanoimprint with UV curable resin, a mold fabricated by etching quartz by using Cr as a hard mask isgenerally used. For fine pattern fabrication, Cr fine pattern etching technology is very important. Usually, therealization of enough resolution needs a resist thickness reduction, which, however, makes it difficult to etchextremely fine Cr features with vertical sidewalls. Here, we propose a brand-new method called "reverse EB process". In this method, an electron-beam (EB)resist pattern is first reversed by a plasma-robust material, with which as a mask, the Cr is then etched to forma hard mask for the mold etching. By this process, we have realized a quartz mold with patterns of 16nm inhalf pitch at minimum.