Nano-Imprint Lithography Using Replicated Mold by Ni Electroforming

Abstract

In nano-imprint lithography, durability of the mold is one of the most important factors for industrial application. We demonstrate replicated mold fabrication for integrated fine patterns based on a Si/SiO2 master mold. The replication is performed by Ni electroless plating and a Ni electroforming process for a 1 in.2 field. Fine patterns as small as 250 nm in width and 270 nm in height have been successfully replicated without fatal defects such as cracks or voids. Using the replicated mold, fine patterns have been successfully obtained by imprint lithography. The surface roughness of the replicated mold is relatively poor compared with that of the master mold because of the micrograins of the Ni electroless plating layer. However, the quantitative values of the surface roughness of both the replicated mold and the imprinted resist are sufficiently small for practical usage.