(Keynote) Atomic Scale and Interface Interactions in Redox-Based Resistive Switching Memories
Redox-based resistive switching memories (ReRAM) are major candidates to fulfil all requirements for low power consumption, ultrafast operation, high information density and non-volatility. Their metal/solid-electrolyte/metal structure makes the preparation process simple and compatible with current CMOS technology. In ReRAMs, the solid electrolyte thickness varies in the range between few nanometers up to some ten nanometers. Due to the small dimensions, the high electric fields in the order of E ~ 108 Vm–1, and current densities of j ~ 109 Acm–2, the interface regions are dynamically changing as a function of the thermodynamic and operation conditions. Deposited as nanoscale films, even macroscopic insulating materials like SiO2 and Ta2O5 are able to conduct ions, and electrochemical measurements well known from the liquid electrochemistry can be performed.
The talk gives an overview on the current state-of-the-art knowledge on redox-based resistive switching ReRAMs, focusing on the electrochemical dynamics at the metal/solid-electrolyte interfaces of nanoscaled thin films and quantum effects. The electrochemical kinetics during formation of nanofilaments will be discussed along with influence of the local environment and the generic relevance of the counter charges. The relation of these studies to the more fundamental issue of describing the microscopic electrochemical processes at the atomic scale will be emphasized.