The Waterloo Institute for Nanotechnology (WIN) presents a seminar by Professor Wei Lu, from the Department of Electrical Engineering and Computer Science, University of Michigan - Ann Arbor, Michigan, United States
Memory and Computing Systems Based on Reconfigurable Materials: Merging Electronics with Ionics
Abstract
Exponential growth of the semiconductor industry, historically driven by transistor scaling, is now facing fundamental challenges. In this talk, I will discuss an emerging class of devices that, by merging electronic with ionics, offer the potential to control the materials’ electronic properties in-situ and have led to promising memory and circuit concepts. These devices exhibit history-dependent, resistive switching behavior and are termed memristors (memory + resistor) or resistive memory devices. I will discuss our efforts on the development and optimization of memristor devices and integrated systems, including techniques of controlling the dynamic ionic migration processes and associated modeling efforts. Detailed TEM studies have been carried out to capture the ionic migration process and verify the switching mechanism. Functional high-density crossbar arrays have been integrated directly on top of CMOS circuits using a back-endof-line (BEOL) process, enabling hybrid non-volatile memory and reconfigurable circuit applications. Properly tuned devices also exhibit incremental conductance changes that are analogous to the behaviors of biological synapses and are well suited for hardwarebased, bio-inspired neuromorphic logic systems. Prototype neuromorphic circuits based on memristor arrays have been shown to be able to perform tasks such as pattern recognition in an unsupervised fashion for intelligent sensing, analysis and other dataintensive applications.
Wei Lu is a Professor at the Electrical Engineering and Computer Science Department at the University of Michigan – Ann Arbor, and Director of the Lurie Nanofabrication facility at UM. He is also co-founder and Chief Scientist of Crossbar Inc, and has been an associate editor for Nanoscale since 2011. He received B.S. degree in physics from Tsinghua University, Beijing, China, in 1996, and Ph.D. in physics from Rice University, Houston, TX in 2003. From 2003 to 2005, he was a postdoctoral research fellow at Harvard University, Cambridge, Massachusetts. He joined the faculty of the University of Michigan in 2005. His research interest includes high-density memory based on two-terminal resistive switches (RRAM), memristor-based neuromorphic circuits, aggressively scaled nanowire transistors, and electrical transport in low-dimensional systems. To date Prof. Lu has published over 100 journal papers with over 16,000 citations and an h-factor of 54. He is also an associate editor for Nanoscale and serves on several IEEE committees. Crossbar Inc, co-founded by Prof. Lu in 2010, is a startup company based in Silicon Valley with $100M VC funding to date and offers commercial RRAM products for embedded and standalone memory applications.