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Title: Molecular Dynamics Study of the Quenching Effect on Direct Nanoimprint of Gold
Nanoimprinting of gold has the potential to make significant impact in the fabrication of miniaturized devices including optical devices, photonic crystals and biochemical sensors. The deformation behavior and recrystallization of gold structures has profound impact on the accurate replication of the imprinted pattern. An important step in the nanoimprint lithography (NIL) process is the cooling of the mold and resist assembly to room temperatures. The rate of cooling, commonly termed as quenching determines the final shape of the NIL features. Molecular dynamics simulations were implemented to study the nanoimprinting of gold substrates using a silicon mold. Simulations were conducted at room temperature (298 K), gold recrystallization (473K) and melting point (1000K) temperatures. The effect of different cooling rates (quenching) on the deformation behavior and spring back of gold was investigated. These include 0.01ns, 0.05ns, and 0.2ns time steps of quenching at 1fs per time step. The modified embedded atom method (MEAM) potential was used for the system molecules. Fast cooling at 298 K and 473 K whereas, intermediate cooling at 1000 K resulted in good pattern transfer. High fidelity nanoscale features were achieved with a gradient cooling proportional to the initial heating temperatures. The findings of this research provide insight on the effect of quenching in the material deformation and spring back during direct metal nanoimprinting.  more » « less
Award ID(s):
1663128
PAR ID:
10119237
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the 2019 IISE Annual Conference
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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