Degradation Studies on 8-Layer 3D Vertical Resistive Random Access Memory Under Moisture

Resistive random-access memory (RRAM) is a promising alternative to Flash memory. For high density application, 3D vertical RRAM (VRRAM) is a cost-effective method that attracts many attentions. However, the VRRAM also has some reliability issues. In this paper, the degradation under moisture stress is studied. High resistant state(HRS) is sensitive to moisture, while the low resistant state(LRS) remains stable. So, the moisture stress decreases the memory window. This degradation is caused by the moisture invasion HfO2/TaOx interface along the side wall and reduce the barrier of the interface. Based on Poole-Frenkel emission, this paper models the degradation mechanism to illustrate the process.