Stepped Identical Reset-Pulse and Lookup Table Programming of Multilevel Conductance in HfOx/AlOy Superlattice-Like Memristors

In this article, we adopted an approach using consistently stepped identical reset-pulses to program the multilevel conductance in HfOx/AlOy superlattice-like memristors. Through the experimental measurements by applying a series of identical reset-pulses, the conductance of memristors is confirmed to converge to a stable and uniform value, with the achieved conductance state depending on the applied pulse amplitude. Later, the adopted programming approach is comprehensively discussed in terms of pulse selection and programming scenarios. Based on the fact the converged conductance is strongly associated with the applied pulse amplitude, the eight-level lookup table programming method is established and applied, and it outperforms the write-verify method in terms of programming complexity, programming variations, and retention performance. The underlying programming mechanism and the memristor evolution process are also discussed.