Switching characteristics in Cu:SiO2 by chemical soak methods for resistive random access memory (ReRAM)

A novel nanoscale‐crossbar resistive switching memory using a copper chemical displacement technique

“…Next, the resistance state was switched back to the HRS through a DC sweep, and the HRS resistance was read at 0.1 V. The nanoscale‐crossbar Cu‐CDT ReRAM device demonstrated a stable data retention property before 1.5 × 10 4 s. The on and off current ratios were maintained at approximately four orders of magnitude and over 10 4 s at 85 °C. However, the degradation phenomenon of the LRS occurred after 1.5 × 10 4 s. This could be ascribed to the metal ion rapid migration during high‐temperature baking, resulting in the thin Cu conductive filament were easily ruptured .…”

Improvement of switching endurance of conducting-bridge random access memory by addition of metal-ion-containing ionic liquid

“…We reported that the reduction of switching voltages and the improvement of an tolerance against external stimuli such as voltage and temperature can be achieved by supplying ionic liquid (IL) to the memory layer of conductive-bridge random access memory (CBRAM) [1]. On the other hand, it was reported that doping of Cu to the memory layer reduced switching voltages and improved the dispersion of the switching voltage and data retention [2,3]. However, the data endurance, at the same time, worsened with increasing the doped Cu concentration, due to the formation of filaments that are too thick to be ruptured for reset [3].…”

“…[8][9][10][11] In addition, it was reported that the doping of Cu to the memory layer of CBRAM reduced switching voltages and improved the dispersion of switching voltages and data retention. 12,13) However, the data endurance, at the same time, worsened with increasing Cu doping concentration, owing to the formation of filaments that are too thick to be ruptured for reset. 13) Owing to these results, we hypothesized that the addition of an appropriate Cu salt solution of IL would improve the cycling endurance as well as the switching voltages and data retention of CBRAM.…”

“…12,13) However, the data endurance, at the same time, worsened with increasing Cu doping concentration, owing to the formation of filaments that are too thick to be ruptured for reset. 13) Owing to these results, we hypothesized that the addition of an appropriate Cu salt solution of IL would improve the cycling endurance as well as the switching voltages and data retention of CBRAM. This hypothesis is based on the expectation that the segregation of Cu, which is the main factor causing reset failure, could be avoided in liquids but not in solids.…”