Fabrication of nanodot array mold with 2 Tdot/in.² for nanoimprint using metallic glass

Here, the authors fabricated a mold consisting of nanodot arrays with an 18-nm pitch and performed nanoimprinting of metallic glass for developing bitpatterned media (BPM) with an areal recording density of 2 Tbit/in. ². Specifically, they investigated the feasibility of SiO ₂/Si mold fabrication by metal mask patterning with focused ion beam assisted chemical vapor deposition (FIB-CVD) and reactive ion etching (RIE). SiO₂ was etched with a mixed gas of CHF₃ and O ₂, resulting in successful fabrication of convex nanodot arrays with an 18-nm pitch. The authors attempted nanoimprinting of Pd-based metallic glass with the fabricated SiO₂ mold and clearly confirmed the replication of the fine nanohole pattern. These results suggest that the proposed FIB-CVD and RIE process is a promising method for fabricating ultrafine nanodot arrays and that metallic glasses are excellent nanoimprintable materials for mass-produced nanodevices such as BPM with ultrahigh recording density.