• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.332-336
• /
• 2007

Temperature is an essential process variable in nanoimprint lithography(NIL) where the temperature varies between room temperature and above the glass transition temperature. To simulate NIL process, we employ both the Nose-Poincare method for temperature controlled molecular dynamics(MD) and force field for polymer material i.e. polymethyl methacrylate(PMMA), which is most widely selected as NIL resist. Nose-Poincare method, which convinces the conservation of Hamiltonian structure and time-reversal symmetry, overcomes the drawbacks inherent in the conventional methods such as Nose thermostat and Nose-Hoover thermostat. Thus, this method exhibits enhanced numerical stability even when the temperature fluctuation is large. To describe PMMA, we adopt the force field which account for bond stretch, bending, torsion, inversion, partial charge, and van der Waals energy.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2007.04a
• /
• pp.433-438
• /
• 2007

Mechanical behavior of copper Nanowire is investigated, An FCC Nanowire model composed of 1,408 atoms is used for NID simulation, Simulations are performed within NVT ensemble setting without periodic boundary conditions, Nose-Poincare MD algorithm is employed to guarantee preservation of Hamiltonian. Numerical tensile tests are carried out with constant strain rate, Stress-strain curve is constructed from the calculated Cauchy stresses and specified strain values, Non-linear behavior appears around $\varepsilon$=0.064, At this instance, starting of structural reorientations are observed.