"Ultra-nonlinear Switching Kinetics of Redox-based Memristive Oxide Elements"

Dr. Rainer Waser , Co-Founder of JARA-FIT

September 8th (Thursday), 3:00pm
Harold Frank Hall (HFH), Rm 1132 (CS Conf. Room)

Redox-Based Resistive Switching Memories (ReRAM), also called nanoionic memories or memristive elements, are widely considered to provide a potential leap beyond the limits of Flash (with respect to write speed, write energies) and DRAM (with respect to scalability, retention times) as well as energy-efficient approaches to neuromorphic concepts.

In this seminar talk, the ultra-high non-linearity of the switching kinetics of redox-based resistive switching devices will be discussed with an emphasis on the so-called valence change mechanism (VCM) typically encountered as a bipolar switching in metal oxides. The involved electrochemical and physical processes can be either electric field/voltage enhanced or accelerated by a local increase in temperature due to Joule heating. The analysis of the published SET switching kinetics data of VCM-type ReRAM systems showed that their nonlinearity is mainly dominated by temperature-accelerated ion hopping, controlled by the local power during the switching process. The gradual RESET transition can be explained in terms of temperature-accelerated ion movement with counter-acting ion drift and diffusion processes. It will be shown that a designated combination of oxides can significantly improve the long-term kinetics, i.e. the retention time, by tailoring the ion diffusion properties in the oxide layers.

About Dr. Rainer Waser :

Image of Rainer Waser Rainer Waser received his PhD in physical chemistry at the University of Darmstadt in 1984, and worked at the Philips Research Laboratory, Aachen, until he was appointed Professor at the faculty for Electrical Engineering and Information Technology of the RWTH Aachen University in 1992 and director of the Institute for Electronic Materials at the Forschungszentrum Jülich, in 1997. He is member of the Emerging Research Devices working group of the ITRS, and he has been collaborating with major semiconductor industries in Europe, the US, and the Far East. Since 2002, he has been the coordinator and spokesman of the research program on Nanoelectronic Systems in Information Technology within the Germany national research centres in the Helmholtz Association. In 2007, he has been co-founder of the Jülich-Aachen Research Alliance, section Fundamentals of Future Information Technology (JARA-FIT). Together with Professor Wuttig, he heads a collaborative research center on resistively switching chalcogenides for future electronics (SFB 917) which comprises of 14 institutes within JARA-FIT and has been funded by the German national science foundation (DFG) since 2011. In 2014, Rainer Waser received the Leibniz Prize of the DFG for his work on the phenomenon of redox-based resistive switching.

Hosted by: Professor Dmitri Strukov