CAREER: Three-Dimensional Nanolithography with Inexpensive Hardware

这笔学院早期职业发展(Career)补助金将开创一种使用光与胶体纳米颗粒相互作用的新型三维纳米光刻系统。在纳米尺度上创建三维物体的能力使得独特的材料特性和设备性能成为可能。然而，几乎所有现有的光刻系统都基于复杂的机械、电子和光学硬件，这些硬件可能昂贵得令人望而却步。该奖项支持基础研究，以提供仅基于胶体-光相互作用的三维纳米光刻所需的知识，而不是目前昂贵的光刻，因此使用廉价的硬件进行纳米光刻。新工艺的重点是胶体纳米颗粒，它将作为基本的构建块，可以操纵和塑造纳米级图案的光。该系统将实现复杂的三维纳米结构的可伸缩打印，用于无针药物输送、多功能材料和可拉伸传感器。这项研究的结果将在生物医学、能源、电子和航空航天行业得到广泛应用，这将有利于美国经济和制造业的发展。这项研究是跨学科的，将进一步加深对纳米技术、物理、材料科学和工程学的理解。综合研究和教育目标将通过K-12学生、教师、家长和当地社区直接参与纳米技术和纳米制造，极大地增加社会上的工程教育。这项研究旨在克服现有3D纳米光刻系统的关键障碍，即操作成本高、图案化分辨率有限和/或制造产能低。最先进的直写方法，如电子束、聚焦离子束、双光子光刻，可以实现良好的特性，并在实验室设备演示中发挥了关键作用。然而，这些系统需要连续图案化和逐层工艺，这是时间密集型的，很难规模化。这项研究不同于传统的硬件密集型光刻方法，而是用胶体纳米颗粒取代它们，胶体纳米颗粒被照明来产生丰富的近场光学纳米颗粒。通过定制灯光属性和粒子参数，这种相互作用将被利用为一种新的机制来设计复杂的3D几何图形。该方法结合了“自下而上”自组装的成本效益，同时保留了“自上而下”光刻的用户指定图案的可控性。研究团队将对近场光-粒子相互作用进行严格的建模，以研究图像形成机制，开发制造工艺以控制结构几何和材料组成，在放大原型系统中减少工艺缺陷并提高成品率，并演示将复杂的3D纳米结构连续打印到新型功能设备中。

This Faculty Early Career Development (CAREER) grant will pioneer a novel three-dimensional nanolithography system using light interactions with colloidal nanoparticles. The ability to create a three-dimensional object at the nanoscale has enabled unique material properties and device performances. However, almost all of the existing lithography systems are based on complicated mechanical, electronic, and optical hardware that can be prohibitively expensive. This award supports fundamental research to provide the required knowledge for three-dimensional nanolithography that is based solely on colloid-light interactions instead of current expensive lithography, hence nanolithography with inexpensive hardware. The new process focuses on colloidal nanoparticles, which will serve as elementary building blocks that can manipulate and shape light for nanoscale patterning. This system will enable scalable printing of complex three-dimensional nanostructures for needleless drug delivery, multifunctional materials, and stretchable sensors. The results of this research will find broad application in biomedical, energy, electronic, and aerospace industries that will benefit the U.S. economy and the advance its manufacturing sector. This research is interdisciplinary and will further understandings in nanotechnology, physics, materials science, and engineering. The integrated research and educational goals will greatly increase engineering education in society through direct engagement of K-12 students, teachers, parents, and the local community in nanotechnology and nanomanufacturing. This research aims to overcome the key barriers to existing 3D nanolithography systems, which can have high operating cost, limited patterning resolution, and/or low fabrication throughput. State-of-the-art direct-write approaches, such as electron-beam, focused-ion-beam, two-photon lithography, can achieve fine features and have played critical roles in laboratory device demonstrations. However, these systems require serial patterning and layer-by-layer processes that are time intensive and difficult to scale. This research diverges from the traditional hardware-intensive approaches to lithography, and replaces them with colloidal nanoparticles that are illuminated to generate a wealth of near-field optical nanopatterns. By tailoring the light properties and particle parameters, such interactions will be harnessed as a novel mechanism to pattern complex 3D geometries. This approach combines the cost-effectiveness of "bottom-up" self-assembly, while retaining the user-specified pattern controllability of "top-down" lithography. The research team will perform rigorous modeling of near-field light-particle interactions to investigate the image formation mechanism, develop fabrication processes to control structure geometry and material composition, mitigate process defects and increase yield in a scale-up prototype system, and demonstrate continuous printing of complex 3D nanostructures into novel functional devices.