Park Jong Han, Lee Ki Yeon, Park Keun
Department of Mechanical System Design Engineering, Seoul National University of Science & Technology, Seoul 139-743, Republic of Korea.
Department of Mechanical System Design Engineering, Seoul National University of Science & Technology, Seoul 139-743, Republic of Korea.
Ultrasonics. 2015 Jul;60:96-102. doi: 10.1016/j.ultras.2015.02.017. Epub 2015 Mar 16.
Ultrasonic imprint lithography (UIL) is a micropattern replication technology on thermoplastic polymers using ultrasonic vibration energy. The UIL process involves three steps: (i) microscale vibration from an ultrasonic horn causes repetitive deformation of a polymer surface, (ii) the polymer surface is locally softened by repetitive deformation and friction, and (iii) micro/nanoscale patterns engraved on the horn or the mold are replicated on the softened substrate. To replicate micro/nano patterns with high accuracy, the effects of various processing conditions should be investigated, and so far, these have been studied experimentally. In this study, coupled numerical analysis was performed using finite element simulation to investigate the heating mechanism of the UIL process, by joining transient structural analysis and heat transfer analysis. The effect of imprinting conditions on the heating capability was investigated using the proposed coupled simulation. The differences between direct and indirect imprinting are also discussed in terms of heating mechanism, and compared with experiments.
超声压印光刻（UIL）是一种利用超声振动能量在热塑性聚合物上进行微图案复制的技术。UIL工艺包括三个步骤：（i）超声变幅杆产生的微观振动使聚合物表面发生反复变形，（ii）聚合物表面通过反复变形和摩擦而局部软化，（iii）刻在变幅杆或模具上的微/纳米级图案被复制到软化的基底上。为了高精度地复制微/纳米图案，应研究各种加工条件的影响，到目前为止，这些都是通过实验进行研究的。在本研究中，通过将瞬态结构分析和传热分析相结合，利用有限元模拟进行了耦合数值分析，以研究UIL工艺的加热机理。利用所提出的耦合模拟研究了压印条件对加热能力的影响。还从加热机理方面讨论了直接压印和间接压印之间的差异，并与实验进行了比较。
