분자 동역학을 이용한 나노임프린트 리소그래피에서의 패턴 전사에 관한 연구

Abstract

The molecular dynamics simulation of nanoimprint lithography (NIL) using SiO₂stamp and amorphous poly-(methylmethacrylate) (PMMA) film is performed to study pattern transfer in NIL. Force fields including bond, angle, torsion, van der Waals and electrostatic potential are used to describe the intermolecular and intramolecular force of PMMA molecules and SiO₂stamp. Nosé-Hoover thermostat is used to control the system temperature and cell multipole method is adopted to treat long range interactions. The deformation of PMMA film is observed during pattern transfer in the NIL process. For the detail analysis of deformation characteristics, the distributions of density and stress in PMMA film are calculated. The adhesion and friction forces are obtained by dividing the PMMA film into subregions and calculating the interacting force between subregion and stamp. Their effects on the pattern transfer are also discussed as varying the indentation depth and speed.