In-Depth Analysis of Transistor Influence on OxRAM Performance in Memory Bitcell, With Technology Scaling Perspectives

An oxide-based random access memory (OxRAM) coupled with a MOSFET selector is widely used in memory bitcell for ReRAM technology, but the consequences of the choice of the selector parameters on the reliability are not fully understood yet. This work has the aim to provide new insights on this topic with a specific focus on scaling perspectives. Accordingly, we go through the characterization of different one-transistor one-resistor (1T1R) structures embedding the same OxRAM and selectors of different sizes where the implication of the selector in set and reset operations is separately analyzed. The set current compliance is found to be the most important metric to control the low-resistive state. The reset analysis demonstrates that the OxRAM will always switch at the same bias independently of the selector once the transistor contribution is compensated. Endurance analysis reveals that an excess of reset bias degrades the cyclability of the system. Thus, we asset that in terms of scaling, the right balance between the transistor properties and the programming conditions have to be taken into account.