Role of the Ta scavenger electrode in the excellent switching control and reliability of a scalable low-current operated TiN\Ta<inf>2</inf>O<inf>5</inf>\Ta RRAM device

Abstract

We engineer a scalable and CMOS-friendly RRAM stack using down to 3nm ALD-based Ta <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> . The 20nm-sized TiN\Ta <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sub> \Ta device operated at 50μA exhibits ultra-fast write (~5ns) at moderate voltage (<;2V) with >10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> 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.