Study on Nanoimprint Lithography of the Polymer Chains (CH₂)_n With Anti-Adhesion Layer on Stamp by Molecular Dynamics Method

This paper aims at the study on nanoimprint lithography (NIL) of the polymer material in (CH₂)_n Chains. The simulation codes were built based on molecular dynamics (MD) method for observing material deformation behaviors in atomic scale. The deformation mechanism of NIL of polymer material (CH₂)_n pressed by silicon stamp was first studied, by which the effects of critical punch tip width, imprint depth, temperature, and adhesion effect were studied. Next, the nanoimprint processes with stamp tips covered by anti-adhesion material, which is a self-assembled monolayer (SAM), were studied to compare to those processes without having anti-adhesion layer. When deforming polymer material at or above room temperature, adhesion problems occur between stamp and polymer. Polymer materials adhere to stamp more severe than they adhere to each others because potential energies between long chains of polymers are smaller than those between polymer and stamp. From the relation between system energy and stamp translation based on the MD simulations, the system energy increases when stamp moves gradually. When unloading, the system energy will return to its minimum energy status and remains stable. However, when punch leaves polymer materials, energy fluctuation occurs due to some polymer materials adhere to the stamp. Finally, the analysis of stamp with and without SAM based on the MD method was conducted and discussed.