CAREER: Rapid Manufacture of Three-Dimensional Nanostructures for Nano-enabled Devices Using Projection Two-Photon Lithography

这项教师早期职业发展（Career）资助的重点是从根本上改变使用双光子光刻技术的复杂纳米结构的三维打印，从缓慢且难以扩展的基于猜测的方法转变为快速且资源高效的基于知识的方法。双光子光刻工艺利用激光直接打印光聚合物中的三维结构，填补了限于平面几何的微制造与典型的增材制造之间的重要技术空白，后者无法打印具有纳米级特征和精度的结构。因此，双光子光刻工艺对于三维纳米器件的制造至关重要，这些器件应用于量子信息处理、电力运输和生物医学等新兴领域，对国家的繁荣和福祉至关重要。然而，由于印刷率低和工艺知识有限，它仍然是一个利基工艺。工业规模的采用尤其具有挑战性，因为在预测所需打印几何形状的过程输入时，涉及到缓慢且劳动密集型的迭代特别实验。该项目阐明了基于投影的双光子光刻高速实现的工艺参数与产品性能之间的基本关系。该研究还通过一项教育和推广计划进行补充，该计划以基于项目的体验式学习为中心，为制造业劳动力、K-12学生和教师、本科生和研究生提供培训，重点是减少先进制造业中多样性、公平性和技能获取的障碍。该研究的具体目标是利用投影双光子光刻技术为纳米结构的高通量三维印刷提供加工科学。该项目推进了三个核心研究领域：(1)高强度光-物质相互作用之间的耦合（接近太瓦/平方厘米），(2)短时间和小长度尺度（即毫秒和亚微米尺度）的聚合，以及(3)聚合对打印纳米尺度特征物理性质的影响。具体的研究目标是：(i)生成基于物理的关系，以预测可打印性和打印几何形状，（ii）阐明决定速率限制的机制，以及（iii）开发误差补偿技术，以最大限度地减少纳米级精度打印大型结构时的缺陷。这项研究试图回答有关这一过程的三个基本问题。(1)能否产生具有广泛普遍性的预测关系？(2)理论和实际的印刷速率限制是什么？(3)误差补偿是否可行？这些问题可以通过对潜在物理现象的基于物理的计算建模、对以前无法测量的经验数据的模型验证以及现场过程监测和控制来解决。该项目使用可扩展的加工技术推进纳米器件的增材纳米制造。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) grant focuses on fundamentally transforming the three-dimensional printing of complex nanostructures using two-photon lithography from a slow and poorly scalable guesswork-based approach to a rapid and resource-efficient knowledge-based approach. The two-photon lithography process, which uses lasers to direct print three-dimensional structures in photopolymers, fills an important technology gap between microfabrication that is limited to planar geometries and typical additive manufacturing that cannot print structures with nanoscale features and precision. The two-photon lithography process is therefore critical for the fabrication of three-dimensional nano-enabled devices with applications in emerging fields such as quantum information processing, electric transportation and biomedicine, which are important to national prosperity and welfare. However, it has remained a niche process due to the low printing rates and limited process knowledge. Industrial-scale adoption is particularly challenging due to the slow and labor-intensive iterative ad-hoc experimentation involved in predicting the process inputs for a desired print geometry. This project elucidates the fundamental relationships between process parameters and product performance for a projection-based high-speed implementation of two-photon lithography. The research is complemented by an educational and outreach program centered around project-based experiential learning for training of manufacturing workforce, K-12 students and teachers, and undergraduate and graduate students, with a focus on reducing the barriers to diversity, equity and skills acquisition in advanced manufacturing. The specific goal of the research is to generate the processing science for high-throughput three-dimensional printing of nanostructures using projection two-photon lithography. This project advances three core research areas: (1) the coupling between light-matter interactions at high intensities (approaching terawatts per square cm), (2) polymerization at short time and small length scales (i.e., on millisecond and submicron scales), and (3) effect of polymerization on the physical properties of the printed nanoscale features. The specific research objectives are: (i) generation of physics-based relationships to predict printability and print geometry, (ii) elucidating the mechanisms that determine the rate limits, and (iii) developing error compensation techniques to minimize defects during printing of large structures with nano-scale precision. The research seeks to answer three fundamental questions about the process. (1) Can broadly generalizable predictive relationships be generated? (2) What are the theoretical and practical printing rate limits? (3) Is error compensation feasible? These are answered through a combination of physics-based computational modeling of the underlying physical phenomena, validation of models against previously unmeasurable empirical data, and in-situ process monitoring and control. This project advances additive nanomanufacturing of nano-enabled devices using scalable processing techniques.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.