Design and fabrication of a metallic nanostamp using UV nanoimprinting and electroforming for replicating discrete track media with feature size of 35 nm

Abstract

The demand for high-density data-storage media is increasing, necessitating the development of novel magnetic data-storage technologies. Among the various types of storage media, discrete track media (DTM) is an emerging technology that is being used to overcome the limitations of conventional continuous magnetic data-storage technology, such as the superparamagnetic effect and medium noise. In this study, the authors propose a method of fabricating a metallic stamp for replicating DTM patterns using ultraviolet (UV) nanoimprinting and electroforming, which are inexpensive processes that can be used to fabricate nanostructures with high precision. First, a silicon nanomaster with a feature size of 35 nm and a pitch of 70 nm was designed and fabricated by electron-beam recording and inductively coupled plasma etching. The measured pitch of the silicon master was 71.6 nm. Then, a polymeric master with a full track of nanoline patterns was then replicated from the silicon nanomaster via UV nanoimprinting. To improve the releasing properties during UV nanoimprinting, the silicon nanomaster was coated with a self-assembled monolayer of fluoroctatrichlorosilane. The measured average pitch and height of the replicated polymer master were 71.5 and 61 nm, respectively. Then, a metallic nanostamp with a thickness of 300 μm and a diameter of 80 mm was fabricated using electroforming. The metallic nanostamp was successfully fabricated, and its geometrical properties were measured and analyzed. The pitch and height of fabricated nickel stamp were 71.2 and 60.3 nm, respectively.