Fabrication of metallic stamp with 30 nm hole array using UV nanoimprinting and nanoelectroforming

With increasing demands for products with nano scale patterns manufactured by nanoreplication processes such as nanoinjection molding, nanoimprinting, and etc, fabrication of molds or stamps with nano patterns has become a priority for successful manufacturing of nano patterned products. In this study, a metallic stamp with nano hole array pattern was fabricated by ultra-violet (UV) nanoimprinting process and nanoelectroforming process. For the fabrication of the original silicon master, electron-beam (E-beam) lithography and inductively coupled plasma (ICP) etching process were used. Polymeric nano pillar array pattern, called polymeric master, was replicated from the original silicon master by UV nanoimprinting process. For the successful demolding during UV nanoimprinting process, self assembled monolayer (SAM) of fluoroctatrichlorosilane (CF₃(CH₂)₈SiCl ₃) was deposited on the original silicon master. With this approach, the expensive silicon master could be reused many times as a master mold. Nickel seed layer as conductive layer was deposited onto the polymeric master using sputtering process. Nanoelectroforming process using nickel sulfamate solution (Ni(NH₂SO₃)₂ 4H₂O) was carried out to fabricate the metallic nano stamp. Metallic nano stamp which has hole array pattern with diameter of 30 nm and pitch of 50 nm was successfully fabricated by the proposed method. Nanoinjection molding of 30 nm pillar array pattern as a nano data storage media using the present metallic stamp is the subject of ongoing research.