HfOx bipolar resistive memory with robust endurance using ZrNx as buttom electrode

The high temperature conducting materials Zirconium nitride (ZrNx) films were deposited on silicon-based substrates as bottom electrodes for resistive random access memory (RRAM) cells in Pt (top)/HfOx(x = 1.7)/ZrNx (bottom) sandwich structure. The reproducible resistive switching (RS) property of the memory cells was studied systematically for RRAM applications. In contrast to the memory cells in Pt/HfOx/Pt structure, the Pt/HfOx/ZrNx structure show a robust endurance, low and stable operation parameters, large memory window and good retention properties. The composition and chemical bonding states of the prepared HfOx and ZrNx thin films were analyzed by X-ray photoelectron spectroscopy (XPS) technique and the cross-sectional image of the Pt/HfOx/ZrNx structure was observed by high-resolution transmission electron microscopy (HR-TEM). The results show that the formed interface Zirconium oxynitride between the dielectric HfOx film and the ZrNx bottom electrode play key roles in the RS performance improvement.