Tuesday, April 16, 2013 - 8:45am to 9:45am
KEC 1007

Speaker Information

Ashkan Behnam
Post-doctoral Research Associate
Department of Electrical Engineering
University of Illinois at Urbana Champaign

Abstract

Due to their superb mechanical, electrical and thermal properties, materials based on carbon nanostructures such as carbon nanotubes and graphene have been considered for various applications either as active materials (e.g. for sensors and flexible electronics) or as electrodes and interconnects (e.g. for memories, heat sinks, and photovoltaic devices). In addition to the need for solving some of the fabrication and integration challenges ahead, electrical and thermal properties of these materials need further analysis in order to evaluate their performance and reliability.

I will first talk about analyzing the transport in families of carbon based materials such as Carbon Nanotube Networks (CNNs) and Graphene Ribbons (GRs) using experimental techniques, as well as analytical and computational modeling. We observe that the transport in CNNs with complex structures depends on various nanotube and network parameters. Our computational results assist in revealing intrinsic electrical/thermal properties of individual elements within CNNs that are otherwise difficult to characterize. We also analyze the high electric field transport in various types of GR interconnects and find them promising and reliable. Breakdown in GRs is decided by Joule heating, and as a result with a small amount of thermal engineering we can achieve record high current densities.

I will also present our results on specific applications for which these materials are suitable candidates. These would include CNN-based FETs for flexible electronics and GR-based sensors. I will conclude the talk by mentioning some of the potential future research directions. These will include analysis of novel 1D and 2D materials for chemical and bio sensing, as well as non-volatile memories and characterization and tuning of physical properties of meta-materials (e.g. composites) based on nanostructures.

Speaker Bio

Dr. Ashkan Behnam has received his Ph.D. in Electrical Engineering (EE) from University of Florida (UF), where he studied transport in carbon nanotube thin film devices. He is currently a post doctoral research associate in EE at University of Illinois at Urbana Champaign (UIUC). His current research focus is on design and implementation of integrated phase-change memory circuits with nanotube/graphene-based interconnects. He is also interested in characterizing and evaluating novel materials for their incorporation into device structures for wearable electronics, sensing and thermoelectric applications. Dr. Behnam is a member of IEEE, MRS and APS and a recipient of the Alumni Fellowship and International Student Outstanding Achievement Award from UF.