Woodruff School of Mechanical Engineering
Faculty Candidate Seminar
Advanced Micro/Nano-Manufacturing Processes: Fabricating Thin Film Devices on Unusual Substrates
Dr. Chi Hwan Lee
Department of Materials Science and Engineering, University of Illinois at Urbana- Champaign
Thursday, February 19, 2015 at 11:00:00 AM
MRDC Building, Room 4211
Dr. Peter Hesketh
Thin film devices consist of semiconductor layer as well as dielectric layer and metallic contacts which are deposited over a supporting substrate, commonly glass or wafer. Fabrication of the thin film devices on unusual yet useful substrates, such as papers, rubbers, plastics and clothes, offers advantages of flexibility, stretchability, wearability, low cost and/or light-weight in actual use. However, the unusual substrates severely suffer from the incompatibility issues with conventional fabrication facilities due to their low thermal/chemical resistance and high surface roughness. This talk introduces advanced micro/nano-manufacturing processes enabling the fabrication of thin film devices on a broad range of unusual substrates. Examples of system-level demonstrations include ‘paper solar cells’, ‘ultrathin nanosensors’, ‘wearable biomedical devices’and ‘bio-dissolvable drug delivery vehicles’ by choosing their supporting substrates according to the applications. Exploiting high quality of semiconducting nanomaterials, such as silicon-based nanowires and nanomembranes, facilitates to achieve high performances comparable to those of the state-of-art devices that are fabricated on conventional rigid, flat substrates. Understanding the basic working principles of underlying mechanics and chemical reactions in the micro/nanomanufacturing processes leads to further improvements in usability, scalability and yields.
Dr. Chi Hwan Lee received M.S. (2009) and Ph.D. degrees (2013) in Mechanical Engineering at Stanford University, and double B.S degrees (2007) in Mechanical Engineering and Industrial Engineering at Illinois Institute of Technology and Ajou University (Korea) through dual degrees program. His Ph.D. research with professor Xiaolin Zheng includes developments and fundamental studies of advanced micro/nano-manufacturing processes for the fabrication of thin film devices on flexible, transparent and/or bio-compatible substrates using micro/nanomaterials as semiconducting components. His current research from August 2013, as a postdoctoral research associate in professor John A. Rogers Group at University of Illinois at Urbana-Champaign, aims to explore novel design layouts, materials, mechanics and processes for biodissolvable thin film devices which are functional for programmed time frames but then completely disappear via chemical resorption. Practical applications using the bio-dissolvable thin film devices include biomedical sensors and drug delivery vehicles.
Refreshments will be served.