Cell-to-cell Fundamental Variability Limits Investigation in OxRRAM arrays

In this paper the fundamental variability limits of filament based OxRRAM are investigated considering different transistor sizes and MIM stacks featuring different materials and thicknesses. Cell-to-cell variability is analyzed through an extensive characterization of Forming, Set and Reset operations on 4kbits OxRRAM arrays. The results obtained in terms of switching voltage variability and resistance variability from cell to cell are compared and discussed to identify the variability limiting component as a function of the conduction regime and to understand the impact of transistor MIM stack parameters on variability and performances.