In-situ TEM observation of Cu/MoOx ReRAM switching

In-situ TEM observation was applied to a miniaturized Cu/MoOx/TiN ReRAM device shaped by the ion-shadow method. Applying a positive voltage to the Cu top electrode, resistive switching from the high-resistance state (HRS) to the low-resistance state (LRS) occurred, and a precipitation appeared in the switching layer of MoOx. On the other hand, negative voltage to Cu erased the precipitation, and the resistance state was converted from LRS to HRS. Growth or contraction of the precipitation was recognized during further voltage application after the switching operation. The precipitation observed in this work is thought to correlate with the resistive switching, and its formation and rupture phenomenon agrees to the switching mechanism based on conductive filaments.