Enhanced stability of complementary resistance switching in the TiN/HfOx/TiN resistive random access memory device via interface engineering

• Main Authors: Ang, Diing Shenp, Zhang, H. Z., Yew, K. S., Wang, X. P.
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2016
• Subjects: Aluminium; Atomic layer deposition
• Online Access: https://hdl.handle.net/10356/81517; http://hdl.handle.net/10220/40833
• Institution: Nanyang Technological University

This study shows that a majority (70%) of TiN/HfOx/TiN devices exhibit failed complementary resistance switching (CRS) after forming. In conjunction with the consistent observation of a large non-polar reset loop in the first post-forming voltage-sweep measurement, it is proposed that breakdown of the TiN/HfOx interfacial oxide layers (crucial in enabling CRS) and the accompanied formation of Ti filaments (due to Ti migration from the TiN cathode into the breakdown path) resulted in CRS failure and the observed non-polar reset behavior. This hypothesis is supported by the significant reduction or complete elimination of the large non-polar reset and CRS failure in devices with a thin Al2O3 layer incorporated at the TiN-cathode/HfOx or both TiN/HfOx interfaces. The higher breakdown field of the thin Al2O3 enables it to sustain the forming voltage until the forming process is interrupted, thus enabling CRS via oxygen exchange with the adjacent vacancy-type filament formed in the HfOx.