Ultrathin (<10nm) Nb<inf>2</inf>O<inf>5</inf>/NbO<inf>2</inf> hybrid memory with both memory and selector characteristics for high density 3D vertically stackable RRAM applications

We report, for the first time, the novel concept of ultrathin (∼10nm) W/NbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf> /Pt device with both threshold switching (TS) and memory switching (MS) characteristics. Excellent TS characteristics of NbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> , such as high temperature stability (∼160°C), fast switching speed (∼22ns), good switching uniformity, and extreme scalability of device area (ϕ∼10nm)/thickness (∼10nm) were obtained. By oxidizing NbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> , we can form ultrathin Nb <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> /NbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> stack layer for hybrid memory devices with both TS and MS. Without additional selector device, 1Kb cross-point hybrid memory device without SET/RESET disturbance up to 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> cycles was demonstrated.