Anti-adhesive effects of diverse self-assembled monolayers in nanoimprint lithography

Nanoimprint lithography is a highly effective method for manufacturing nanostructures. Although it is an excellent replication technique, the imprinted polymer adheres to the mold into which it is inserted, causing a severe problem. Numerous elementary experiments were performed to evaluate this phenomenon. For example, self-assembled monolayers such as CH3(CH2)17SiCl3 (OTS) and CF3(CF2)7(CH2)2SiCl3 (FDTS) are adopted as an anti-adhesive layer to increase the lifetime of the mold. Processing conditions are presented and the obtained results discussed. Consequently, the height and size of the OTS layer increase with the deposition temperature. After 17 imprint cycles, the amount of polymer residue was least on the mold coated with OTS, immersed in toluene at 25 °C in 20% humidity. The same result was obtained using a mold coated with FDTS. The anti-adhesive efficacy of FDTS is almost constant even as the temperature increased to 300 °C. This anti-adhesive monolayer may be the best choice for high-temperature nanoimprinting.