Nanoimprinting of Thin Polymer Films Using Elementwise Patterned Stamp and Subsequent Application of Pressurized Air

Abstract

To improve the throughput of ultraviolet nanoimprint lithography (UV-NIL), a cost-effective method of fabricating sub-100-nm-wide line patterns, research studies have been focused on employing a large-area nanostamp. In this paper, we present a new single-step UV-NIL process in which an elementwise patterned stamp (EPS), a 5''×5'' quartz stamp, is first used to imprint resin droplets against a 4'' Si wafer. The EPS consists of 16 elements, each of which is 10×10 mm2, i.e., the effective pattern area is 1,600 mm3. Pressurized air is subsequently applied to the bottom of wafer to improve directly the contact between the wafer and the elements, and resultantly, the uniformity of residual layer thickness. To examine the effects of the pressurized air on the uniformity, we have carried out experiments. Resin droplets with a viscosity of 7 mPa s were dispensed on each element. Results show that the air pressure range of 0.05–0.2 MPa does not significantly affect the average thickness distribution but the uniformity. Line patterns of 70 nm width were successfully imprinted at an air pressure of 0.1 MPa.