Interface engineering for improving reliability of resistance switching in Cu/HfO2/TiO2/Pt structure.

Reliability and uniformity in resistance switching behaviours in top electrode Cu-sputtered TiO₂-bottom electrode Pt memory structure were greatly improved by inserting an interface layer of 5nm-thick HfO₂ between Cu and 50nm-thick TiO₂. The thin HfO₂ layer, with much smaller cluster size than TiO₂, limited the Cu migration appropriately and induced more uniform Cu conducting filament distribution. The repeated rejuvenation and rupture of Cu filament was limited within the HfO₂ layer, thereby improving the switching reliability and uniformity. This also greatly decreased operation power compared to a memory cell without the thin HfO₂ layer. [ABSTRACT FROM AUTHOR]