Role of the Ta scavenger electrode in the excellent switching control and reliability of a scalable low-current operated TiN\Ta2O5\Ta RRAM device

Abstract

We engineer a scalable and CMOS-friendly RRAM stack using down to 3nm ALD-based Ta₂O₅. The 20nm-sized TiN\Ta₂O₅\Ta device operated at 50μA exhibits ultra-fast write (~5ns) at moderate voltage (<;2V) with >10⁹ write endurance. We also demonstrate excellent disturb and retention characteristics, which we relate to the appropriate tuning of the oxygen chemical-potential profile along the filament by means of the Ta scavenger material and thickness.