CAREER: Large Scale Manufacturing of Metasurfaces Using Microsphere Photolithography

该学院早期职业发展(Career)项目的研究目标是产生必要的基础制造科学，以经济地创造大规模的超表面。超表面是一种从微米级到纳米级的结构化表面，可以产生超出自然界可用范围的电磁特性，具有许多潜在的基础应用，包括增强热传递、提高气体传感器的检测极限和超薄光学器件。使用传统的基于光刻的方法，变形表面非常昂贵，因此通常只在厘米级生产以用于实验室演示。该项目将创造强调微球光刻(MPL)的新制造技术，该技术使用自组装的微球将光子喷射聚焦到光致抗蚀剂层中，在表面产生凹痕。随后，球体被移除以揭示图案。该项目将严格确定MPL的工艺-结构-表面性能关系，并建立扩大到大规模生产的途径，包括卷筒到卷筒印刷和电铸。综合教育计划将通过允许学生设计/制造/测试设备来吸引他们，这些设备展示了与亚微米结构相关的性能改善，但规模是他们可以处理的。特别强调的是增加第一代、农村、大学生和少数族裔对工程的参与，以及为迅速崛起的先进光学部门培养训练有素的劳动力。这项研究将创建一个使用微球光刻(MPL)制造的框架。该项目需要四个研究目标(1)使用MPL生成复杂的超表面，(2)通过改进的自组装和测量来提高工艺的产量，(3)使用可重复使用的掩模(包括卷到卷配置)来扩展工艺，以及(4)将MPL方法与电沉积相结合研究还将为工艺生成精确的基于物理的模型，包括法向和离轴照明的影响。这将促进更好的变形表面性能，并在典型试验台的背景下解决可扩展的低成本制造微到纳米结构的关键问题，包括增强建筑物的辐射冷却和平面光学。研究成果将是关于材料/光子射流相互作用的新知识，显著改善了制作超表面和类似结构的制造平台。

The research objective of this Faculty Early Career Development (CAREER) project is to generate the fundamental manufacturing science necessary to economically create metasurfaces at large scales. Metasurfaces are microscale-to-nanoscale structured surfaces that are engineered to produce electromagnetic properties beyond what is available in nature, and have many potential fundamental applications applications including enhancing heat transfer, increasing the detection limits of gas sensors, and ultrathin optical devices. Using conventional lithography-based approaches, metasurfaces are very expensive, and as a result are generally produced only at the centimeter scale for laboratory demonstrations. This project will create new manufacturing techniques emphasizing Microsphere Photolithography (MPL), which uses self-assembled microspheres to focus photonic jets into a photoresist layer, generating indentations in the surface. The spheres are subsequently removed to reveal the pattern. The project will rigorously determine the process-structure-metasurface performance relationships for MPL and establish pathways to scale-up to mass production, including roll-to-roll printing and electroforming. The integrated education program will engage students by allowing them to design/build/test devices that demonstrate the improved performance associated with sub-micron structures but at scales that they can handle. A particular emphasis is placed on increasing the involvement of first generation, rural, college students and underrepresented minorities in engineering as well as developing a trained workforce for the rapidly emerging advanced optics sector. This research will create a framework for manufacturing using Microsphere Photolithography (MPL). The project entails four research objectives (1) generation of complex metasurfaces using MPL, (2) improving the yield of the process through improved self-assembly and metrology, (3) scaling the process using reusable masks including a roll-to-roll configuration and (4) integrating the MPL approach with electrodeposition The research will also generate accurate physics based models for the process, including the effects of normal and off-axis illumination. This will facilitate better metasurface performance and address the critical problem of scalable low-cost manufacturing of micro-to-nanostructures in the context of representative test-beds including enhanced radiative cooling of buildings, and planar optics. The research outcomes will be new knowledge about the material/photonic jet interaction, significantly improving the manufacturing platform for the fabrication of metasurfaces and similar structures.