Abstract:
Polymer shrinkage becomes a new approach to do lithography and generate smaller structures by reforming larger pre-patterned structures. The facile polymer fabrication approach by embossing and thermoplastic shrinkage aims to do lithography in a nanoscale or reduce the feature size and dramatically increase the aspect ratio of imprinted microstructures. The shrinkage capability of embossed microstructures is reserved by molding at low temperatures for less cycle time. Embossed patterns are activated for shrinkage by removing projected structures and heating at higher temperatures. The final structures are defined with the shape of removed materials before shrinking polymer materials. Both two- and three-dimensional hot embossed structures were successfully shrunk into much smaller scale. This polymer-shrinking process brings a new way to extend the fabrication capability of polymer embossing process. This talk will present shrink polymer for nanolithography, high-aspect-ratio microstructures, high-performance biosensors, and high-efficiency solar cells.
Biography:
Tianhong Cui is currently a Professor of Mechanical Engineering and an Affiliate Senior Member of the graduate faculty in Department of Electrical and Computer Engineering and Department of Biomedical Engineering at the University of Minnesota. He joined the faculty of the University of Minnesota in 2003. From 1995 to 2003, he held research or faculty positions at Tsinghua University, University of Minnesota, National Laboratory of Metrology in Japan, and Louisiana Tech University, respectively.
His current research interests include MEMS/ NEMS and nanotechnology. He has more than 260 publications in MEMS and nanotechnology. His research has been sponsored by NSF, DARPA, NASA, DOE, etc. He received research awards including the STA & NEDO fellowships in Japan, the Alexander von Humboldt Fellowship in Germany, the Research Foundation Award from Louisiana Tech University, the Richard & Barbara Endowed Chair from the University of Minnesota, and numerous best paper awards. He is serving as an associate editor for Journal of Nanoscience and Nanotechnology and Journal of Nano Research, and was an associate editor for IEEE Sensors Journal. He is serving as an Executive Editor-in-Chief for two Nature journals, Light: Science & Applications and Microsystems & Nanoengineering.