Experimental study of the series resistance effect and its impact on the compact modeling of the conduction characteristics of HfO₂-based resistive switching memories

The relevance of the intrinsic series resistance effect in the context of resistive random access memory (RRAM) compact modeling is investigated. This resistance notably affects the conduction characteristic of resistive switching memories so that it becomes an essential factor to consider when fitting experimental data, especially those coming from devices exhibiting the so-called snapback and snapforward effects. A thorough description of the resistance value extraction procedure and an analysis of the connection of this value with the set and reset transition voltages in HfO2-based valence change memories are presented. Furthermore, in order to illustrate the importance of this feature in the shape of the I-V curve, the Stanford model for RRAM devices is enhanced by incorporating the series resistance as an additional parameter in the Verilog-A model script.