Fabrication of 10-nm-Order Block Copolymer Self-Assembled Nanodots for High-Density Magnetic Recording

Abstract

In this work, we investigated the fabrication of 10-nm-order block copolymer self-assembled nanodots using high-etching-selectivity polystyrene–poly(dimethylsiloxane) (PS–PDMS) block copolymers for high-density storage devices. We adopted PS–PDMS polymers with two different molecular weights of 13,500–4,000 and 11,700–2,900. With decreasing molecular weight, the nanodot size decreased from 12 to 10 nm, and the pitch correspondingly decreased from 22 to 20 nm. The PS–PDMS film thickness is the critical-factor to determine whether nanodot arrays can form on a large area or not. It was demonstrated that the thicknesses of 36 and 33 nm were optimal for the PS–PDMS polymers of 13,500–4,000 and 11,700–2,900, respectively. The limitation in the selection of PS–PDMS to form a smaller size of self-assembled nanodots is also predicted. This work promises to open way toward 1.6 Tbit/in.2 storage device with cheap cost production.