GOALI: Electrohydrodynamic Force Assisted Nanoimprint Lithography for Defect-Free Nanomanufacturing

为了实现基于新兴纳米结构的商业可行器件的可扩展制造，例如计算机芯片中的纳米电子元件，可以提高数据存储能力的纳米存储单元（或介质），以及用于提高太阳能电池功率效率的光子纳米结构，越来越需要具有成本效益的纳米光刻技术。近年来，纳米压印技术已被业界作为一种重要的候选纳米制造技术来制作这类纳米结构。尽管目前的纳米印迹系统具有加工成本低、图形分辨率高、通量高等优点，但其纳米级缺陷严重限制了工艺收率，严重阻碍了工业应用。该学术与工业联络资助机会（GOALI）奖将寻求建立能够减少或消除此类缺陷的新纳米制造方法。研究课题涉及多个科学和工程学科，包括纳米制造、静电学、流体动力学、仿真和工艺表征。这些学科将被整合起来，为广泛的人群提供跨学科的知识，包括K-12学生和教育工作者、本科生、毕业生以及来自代表性不足群体的学生。该项目还将涉及与工业界的合作，以确保所开发的技术具有可扩展性和商业相关性。目前，压印抗蚀剂薄膜中的纳米气泡是影响制造级纳米压印系统成品率的最严重缺陷之一。研究小组的初步研究表明，这种纳米级缺陷的形成主要是由于纳米结构上的抗蚀剂扩散边缘的表面钉住或模具-衬底界面上的污染物。然而，仍然缺乏有效的方法来消除这种有害的钉住效应和由此产生的气体缺陷。在这个项目中，研究团队的目标是通过创建和研究一种基于纳米级电流体动力学效应的新型光固化纳米压印技术来缩小这一知识差距，该技术有望改善抗填充特性，显著减少或消除纳米级气体缺陷，从而大大提高大面积压印纳米结构的产量。特别是，他们将建立分子动力学模型来研究电流体动力对纳米级气体缺陷动态演化的影响；建立电流体动力辅助纳米压印系统，用于确定和测试无缺陷纳米制造机构；并结合建模和实验数据对仿真模型进行细化。

Cost-effective nanolithography technologies are increasingly needed for realizing scalable manufacturing of commercially-viable devices based on emerging nanostructures, such as nanoelectronic components in computer chips, nanoscale memory cells (or media) that can result in improved data storage capability, and photonic nanostructures for improving the power efficiency of solar cells. Recently, nanoimprint lithography has been adopted by the industry as an important candidate nanomanufacturing technology for patterning such nanostructures. Despite its advantages such as low processing cost, high patterning resolution, and high throughput, the current nanoimprinting systems suffer from nanoscale defects, which have seriously limited process yields and significantly hindered industrial applications. This Grant Opportunity for Academic Liaison with Industry (GOALI) award will seek to establish new nanomanufacturing methods capable of reducing or eliminating such defects. The research topics span over multiple disciplines of science and engineering including nanomanufacturing, electrostatics, hydrodynamics, simulation, and process characterization. These disciplines will be integrated to provide interdisciplinary knowledge to a broad range of people including K-12 students and educators, undergraduates, graduates, and students from underrepresented groups. This project will also involve collaboration with industry to ensure the technologies developed are scalable and commercially relevant. Currently, nanoscale gas bubbles trapped in imprint resist films are one of the most serious defects that affect the yields of manufacturing-grade nanoimprint systems. The research team's preliminary study demonstrates that the formation of such nanoscale defects is mainly attributed to surface pinning of resist spreading edges at the nanostructures or contaminants on the mold-substrate interfaces. However, there is still a lack of effective methods to eliminate such detrimental pinning effects and resulting gas defects. In this project, the research team aims to close this knowledge gap by creating and investigating a new light-curable nanoimprint technology based on nanoscopic electrohydrodynamic effects, which is anticipated to improve resist filling characteristics, significantly reduce or eliminate nanoscale gas defects, and therefore greatly enhance the yields of imprinted nanostructures over large areas. In particular, they will construct molecular dynamics models for investigating the effects of electrohydrodynamic forces on the dynamic evolution of nanoscale gas defects; build an electrohydrodynamic force-assisted nanoimprint system for determining and testing defect-free nanomanufacturing mechanisms; and combine modeling and experimental data to refine the simulation models.