A two-step set operation for highly uniform resistive swtiching ReRAM by controllable filament

For the first time, we demonstrate filament controllability by a two-step set operation based on triple-layer ReRAM. Hence, we report a highly reliable memory switching of a triple-layer structure based on resistive switching memory devices by inserting an additional binary metal oxide layer. The inserted oxide layer in the triple-layer can act as a filament controlling factor with the two-step set operation for reliable resistive switching. Compared with the bi-layer structure, the three layers of the two-step set operation showed excellent uniform V_set, Vreset, high-resistance state (R_HRS), and low-resistance state (R_LRS). Furthermore, the devices exhibited excellent memory performance such as endurance, resistance on/off ratio, and reliable data retention of up to 10⁴ s at 180°C.