Scalable Nanomanufacturing of Optical Metasurfaces by Hierarchical Printing and Predictive Modeling

University Of Washington, Seattle WA

Investigators

Abstract

Optical metasurfaces are designed to steer and control light and images instantaneously. They enable applications ranging from thinner, lighter smartphones to ultrafast image processing for self-driving cars and industrial robots. Processes used today to make optical metasurfaces are slow and costly, preventing their wide scale use in products. This grant investigates a new process to manufacture optical metasurfaces. The process, called scalable nanomanufacturing by hierarchical printing, involves rapidly rolling special stamps onto transparent sheets to produce nanotextured surfaces at large scale, thus minimizing manufacturing waste and cost. High speed digital inkjet printing with special inks is then used to modify these metasurfaces to manipulate light, turning the sheets into surfaces that can perform different functions. For this to become a reality, research on coatings with special properties that allow them to be rapidly nanotextured is performed. This project also studies interactions between printing ink and nanotextured surfaces, a critical element of the approach. The availability of highly functional metasurface photonic elements for applications such as planar cameras, medical diagnostics and optical computing greatly impacts the nation's prosperity, health and security. This grant engages underrepresented youth in science and engineering through the outreach work of full-time graduate students working on this project. The combination of technology-driven manufacturing and education in this work makes economic and societal impact by expanding a high productivity, technology-driven US manufacturing base and workforce. Scalable nanomanufacturing of 2D optical metasurfaces by a hierarchical printing process could lead to new classes of low cost, ultrathin, photonics for applications in energy, information processing, and communication as well as provide insights into nanoscale fluid and surface phenomena which can expand the further adoption of hierarchical nanomanufacuring. This project's scope is broken down into four areas. The first thrust is to develop a predictive computational model for the wetting of femtoliter printed droplets on nanoimprinted surfaces. Secondly, the results from the predictive model are used to guide experimental studies and manufacturing research towards scalably fabricating digitally-modified 2D periodic nanostructure surfaces in an inexpensive process that uses high-resolution inkjet printing. This hierarchical printing imparts digitally-customizable photonic functions to the metasurfaces by depositing localized phase shift modifiers at low-cost. The third and fourth thrusts provide initial designs for the optical meta-elements, characterize the properties of these hierarchically printed structures and provide feedback to guide further study and development of the nanomanufacturing process. 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.