Plasma treatment of HfO2-based metal–insulator–metal resistive memories

This work focuses on Au/HfO2/TiN nonvolatile resistive memory [resistive random access memories (RRAMs)] stacks, where HfO2 is deposited by the atomic layer deposition technique on TiN electrodes. For as-grown RRAMs, no Reset is observed (the structure remains locked in a low resistive state). It is observed that an NH3 plasma treatment of the HfO2/TiN bilayer can restore a Reset stage. X-ray photoelectron spectroscopy analyses showed that the Reset recovery is related to a modification of the HfO2/TiN interface via transformation of the TiON interfacial layer. Thus, postdeposition plasma treatments of the oxide/electrode interface are identified as a valuable tool to improve the switching properties of oxide-based RRAMs.