CAREER: Three-Dimensional Nanolithography with Inexpensive Hardware

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.