Fri, Jan 27, 2017 @ 02:00 PM - 03:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Speaker: Mark Hersam, Northwestern University
Talk Title: Processing and Applications of Two-Dimensional Nanoelectronic Heterostructures
Abstract: Two-dimensional (2D) materials have emerged as promising candidates for next-generation nanoelectronics. As is common for new materials, much of the early work has focused on measuring intrinsic properties on small samples under idealized conditions. However, real-world devices inevitably require large-area samples that are integrated with dielectrics, contacts, and other semiconductors in ambient conditions. This talk will thus explore scalable solution-processing of 2D materials with an eye toward realizing large-area thin-films. For example, density gradient ultracentrifugation allows the solution-based isolation of transition metal dichalcogenides and boron nitride with homogeneous thickness down to the single-layer level. Similarly, 2D black phosphorus is isolated in solution with the resulting flakes showing field-effect transistor mobilities and on/off ratios that are comparable to micromechanically exfoliated flakes. In addition to solution processing, this talk will also report on the integration of 2D materials with dielectrics and other semiconductors. In particular, atomic layer deposition of dielectrics and covalent organic adlayers on 2D black phosphorus suppresses ambient degradation, thereby preserving electronic properties in field-effect transistors at atmospheric pressure conditions. Finally, gate-tunable p-n heterojunction diodes with Type I and Type II band alignments are demonstrated by integrating n-type single-layer MoS2 with p-type semiconducting single-walled carbon nanotubes and pentacene, respectively.
Biography: Mark C. Hersam is the Walter P. Murphy Professor of Materials Science and Engineering and Director of the Materials Research Center at Northwestern University. He also holds faculty appointments in the Departments of Chemistry, Applied Physics, Medicine, and Electrical Engineering and Computer Science. He earned a B.S. in Electrical Engineering from the University of Illinois at Urbana-Champaign (UIUC) in 1996, M.Phil. in Physics from the University of Cambridge (UK) in 1997, and a Ph.D. in Electrical Engineering from UIUC in 2000. His research interests include nanofabrication, scanning probe microscopy, semiconductor surfaces, and nanoelectronic materials. Dr. Hersam has received several honors including the Presidential Early Career Award for Scientists and Engineers, TMS Robert Lansing Hardy Award, AVS Peter Mark Award, MRS Outstanding Young Investigator, U.S. Science Envoy, MacArthur Fellowship, and six Teacher of the Year Awards. Dr. Hersam is the co-founder of NanoIntegris, which is a commercial supplier of nanoelectronic materials. Dr. Hersam is a Fellow of MRS, AVS, APS, AAAS, SPIE, and IEEE, and also serves as an Associate Editor of ACS Nano.
Audiences: Everyone Is Invited
Contact: Marilyn Poplawski