Study on Photoresist Transfer in Rotational Near-Field Photolithography Using Molecular Dynamics Simulation

Rotational near-field photolithography (RNFP) has a great potential for nanostructure fabrication. However, photoresist may be transferred between head and disk resulting in failure of the photolithography process. Two models of photoresist transfer from a rotating disk to a photolithography head were developed using molecular dynamics simulation. The simulation results revealed that photoresist transfer is mainly caused by the strong attraction between the hydrogen atoms in the photoresist and the chromium of the head. When the distance between disk and head is less than the critical flying height, the transfer amount increases with the decrease of rotational speed and flying height. Maintaining the flying height above the critical value is the most effective way to ensure the non-transfer of photoresist.