Complementary Resistive Switching in Niobium Oxide-Based Resistive Memory Devices

Abstract

For the applications of resistive random access memory (RRAM), we study the complementary resistive switch (CRS) behavior of a bilayer Nb <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> /NbO <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</i> RRAM. The CRS effect is explained by the redistribution of oxygen vacancies inside the two niobium oxide layers. Improved CRS effects were observed using W top electrode (TE) instead of Pt, which can be attributed to the oxygen barrier layer derived from a self-formed WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> layer between the W TE and the Nb <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> oxide film. The niobium oxide-based CRS devices within a single memory cell can be directly integrated into a crossbar memory array without the need of extra diodes; this can significantly reduce the fabrication complexity.