Electrically Gated Nanoporous Membranes for Smart Molecular Flow Control
Sungho Kim1), Jeffrey A. Weldon2),
1) Holonyak Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, USA
2) Department of Electrical Engineering, University of Hawaii at Manoa, Honolulu, HI, USA
jaweldon@hawaii.edu
Abstract
Advances in nanofabrication techniques have allowed producing fluidic channels of sub-100nm dimensions with a multitude of potential applications for biosensing, on-chip analytics, and drug delivery. When the dimension of the fluidic channel is comparable to the electrical double layer (EDL) thickness, known as the Debye length, an overlap of EDL is generated in the nanochannel. In the overlap of EDL, there exists an enrichment of counter-ions and the exclusion of co-ions that are caused by electrostatic interactions. In this talk, we will present a novel conductive nanoporous membrane platform that is based on the electrical control of the diffusive transport of charged molecules through gated nanopores by altering the EDL with an external gate voltage. A computational model of the single gated nanochannel was established to quantitatively predict the field-effect gating of the charged molecule transport through the nanochannel. Based on the results of the simulation, we developed a novel conductive nanoporous membrane and achieved electrical control of the molecular flow through the membrane. We sputter-deposited chromium (Cr) – gold (Au) – chromium (Cr) on top of the commercial anodic aluminum oxide nanoporous membrane. The exterior chromium layer was left to oxidize creating the insulation layer for the gate electrode. The novel conductive nanoporous membrane was utilized to create a nanofluidic diode and a novel double-gated nanoporous membrane structure for a biomimetic AND nanofluidic logic gate.
Short Bio
Sungho Kim is a postdoctoral research associate of Holonyak Micro and Nanotechnology Laboratory at University of Illinois at Urbana-Champaign. He received a B.S. and M.S. degree in electrical engineering from Seoul National University, Seoul, Korea, in 2011 and 2013, respectively and the Ph.D. in Electrical and Computer Engineering from Carnegie Mellon University. His research interests include nanofluidics, drug delivery, nanofabrication, and biomedical devices. Currently he is working on developing the silicon neural probes that can be implanted into the brain to collect chemical information on neural activity.
Jeffrey Weldon is an associate professor in the Department of Electrical Engineering at the University of Hawaii at Manoa. Dr. Weldon joined the faculty at the University of Hawaii in 2017. Prior to joining the faculty he was the Sathaye Early Career Professor in the Department of Electrical and Computer Engineering at Carnegie Mellon University. Jeffrey Weldon received the B.S. degree in engineering physics from the University of California, Berkeley and the Ph.D. degree in electrical engineering from the University of California, Berkeley, in 2005. From 2006 to 2010 he was a postdoctoral scholar at the Center for Integrated Nanomechanical Systems. His doctoral research in the area of RF CMOS integrated circuits has been widely adopted by industry and is frequently cited in journals and conferences. His postdoctoral research on the carbon nanotube radio was extensively covered by the popular and scientific press, including Scientific American. His current research interests include nanoscale device design in emerging technologies, heterogeneous integration with CMOS for data-intensive applications and applications of nanotechnology to biomedical devices. Dr. Weldon received the 2001 ISSCC Lewis Winner Award for Outstanding Paper and was the recipient of the 1998 ISSCC Jack Kilby Award for Outstanding Student Paper.