Improved Resistive Switching Uniformity in $ \hbox{Cu/HfO}_{2}/\hbox{Pt}$ Devices by Using Current Sweeping Mode

Abstract

In this letter, current sweeping programming mode is proposed as an efficient method to improve the uniformity of the switching properties of resistive memory devices. Based on the measurement results of the reset process of filament-based <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$ \hbox{Cu}/\hbox{HfO}_{2}/\hbox{Pt}$</tex></formula> devices, current sweeping mode (CSM) can significantly reduce the distributions of <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$R_{\rm off}$</tex></formula> values, as compared with the standard voltage sweeping mode. The improvement is attributed to the elimination of the intermediate resistive states due to the positive feedback of joule heat generation by the use of current sweeping. Furthermore, the uniform distribution of the <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$V_{\rm set}$</tex></formula> values of the set process is also obtained by current sweeping, which stems from the localization of conductive filaments formation and rupture. CSM provides an effective way to achieve uniform resistance state of memory cell.