Thermal imprinting of nano-patterns using thiol-based self-assembled monolayer-treated nickel template

A highly durable imprint template is essential for the industrialization of nanoimprint lithography (NIL). Conventionally, Si-based materials were used for the fabrication of imprint templates. However, their fabrication is very expensive and they can be easily damaged during repeated imprint processes due to their brittleness and poor mechanical properties. The Ni template has excellent mechanical strength and can be easily and cheaply duplicated by the electroforming process. It has the potential for application to the NIL process if its poor antistiction property, which causes serious detaching issues, is improved. In this study, thin Au and Ti layers were deposited on a Ni template and a thiol-based, hydrophobic, self-assembled monolayer (SAM) layer was stably formed on the Au coated Ni template. Thus, the antistiction property of the Ni template was drastically elevated. Using the prepolymer-based, thermal imprint process and the thiol-based, SAM-coated Ni template, sub-micron sized patterns were successfully formed on the Si substrate.