Stack optimization of oxide-based RRAM for fast write speed (<1 μs) at low operating current (<10 μA)

In this paper we engineer a TiN⧹Al2O3⧹(Hf,Al)O2⧹Ta2O5⧹Hf Oxide Resistive Random Access Memory (OxRRAM) device for fast switching at low operation current without sacrificing the retention and endurance properties. The integrated 40 nm × 40 nm cell switches at 10 μA using write pulses shorter than 100 ns (resp. 1 μs) for Reset (resp. Set) and with amplitude <2 V. Using these conditions in a specially developed verify algorithm, a resistive window of 10× is reliably obtained, decreasing the write speed by more than 1 decade compared to state-of-the-art OxRRAM stacks at same current level.