Self-Rectifying Al <sub>2</sub> O <sub>3</sub> /TaO <i> <sub>x</sub> </i> Memristor With Gradual Operation at Low Current by Interfacial Layer
Xuanyu Zhao, Kailiang Zhang, Kai Hu, Yujian Zhang, Qiaozhen Zhou, Zhenhua Wang, Yu She, Zhenzhong Zhang, Fang Wang
Abstract
Sneak path current phenomenon in a memristor array based on cross-point structure could lead to crosstalk, which limits its application in high-density large-scale arrays. Self-rectifying devices are the best choice for suppressing leakage currents without compromising the original performance of the device. It eliminates the need for selectors and effectively reduces process costs. In this work, a self-rectifying memristor based on Au/TaO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><i>x</i></sub> /Al <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">3</sub> /TiN is proposed. Nonlinearity of ~236.76 with a sneak current below 1 nA with a tunable conductance under <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1 \boldsymbol {\mu } \text{A}$ </tex-math></inline-formula> compliance current by introducing a rectifying switching mode after constructing the TaO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><i>x</i></sub> /Al <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">3</sub> different stoichiometric stack. Detailed analysis suggested that the interface barrier and the vacancy-related defects in Al <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">3</sub> are responsible for the special behavior. The effective array scale up to ~400 by readout margin calculation further confirms that the memristor can restrain the sneak current. Our self-rectifying memristor simplifies the device design of subsequent arrays, paving the way for addressing applications in highly compact scenes.