Imprint Lithography with Pressing at Room Temperature

Abstract

Imprint lithography was demonstrated by combining pressing at room temperature and successive developing of photoresist. Two-dimensional gratings with a pitch of 1000 nm and a height of 300 nm formed on a soft mold such as a polyester sheet were transferred onto novolak-type photoresist. By using the patterned novolak-type photoresist as an etching mask, a thermally oxidized 320-nm-thick layer on a Si substrate was etched by reactive ion etching with gas. Through this fabrication process, holes with 450-nm radius and 320-nm depth were obtained on the thermally oxidized 320-nm-thick layer. Because soft molds are usually much more inexpensive than hard molds, applications of imprint lithography are expected to expand. Also, because neither heating systems nor UV light exposure systems are needed in our approach, imprint lithography systems are simplified and costs for imprint lithography systems are expected to be low.