Non-filamentary memristive switching in Pt/CuOx/Si/Pt systems

TL;DR

This study demonstrates a non-filamentary memristive switching mechanism in Pt/CuOx/Si/Pt devices, highlighting a gradual electroforming process and proposing a model based on ion drift and interface changes, advancing the development of uniform, forming-free memristive devices.

Contribution

It introduces a non-filamentary switching mechanism in Cu-based devices and proposes a new model involving ion drift and interface modifications, differing from filamentary systems.

Findings

Non-filamentary switching observed in Pt/CuOx/Si/Pt devices.

Gradual electroforming characterized by resistance increase and capacitance decrease.

Proposed model based on Cu ion and oxygen vacancy drift at the interface.

Abstract

We report a memristive switching effect in the Pt/CuOx/Si/Pt devices prepared by rf sputtering technique at room temperature. Different from other Cu-based switching systems, the devices show a non-filamentary switching effect. A gradual electroforming marked by resistance increasing and capacitance decreasing is observed in current-voltage and capacitance characteristics. By the Auger electron spectroscopy analysis, a model based on Cu ion and oxygen vacancy drift, and thickness change of the SiOx layer at the CuOx/Si interface was proposed for the memristive switching and gradual electroforming, respectively. The present work would be meaningful for the preparation of forming-free and homogeneous memristive devices.