Resistive Switching Characteristics of Hydrogen Peroxide Surface Oxidized ZnO-Based Transparent Resistive Memory Devices

Abstract

Transparent resistive memory technology has gained a huge interest in these recent years not only due to its potential application for future non-volatile memory but also due to its potential as an embedded device in wearable electronics.1 The impact of hydrogen peroxide treatment on the surface of ZnO film used for transparent resistive memory device application has been investigated. The surface oxidation was conducted by immersing the ZnO film into hydrogen peroxide solution. Switching characteristics of as-deposited and surface treated devices were initiated by double forming programming. Based on our previous result, superior memory performance can be achieved when the bipolar forming process is initiated to activate the switching behavior.2 However, in this experiment, such bipolar forming process cannot be performed on the as-deposited device (Fig 1a). Interestingly, after hydrogen peroxide surface treatment, the device is able to perform successful bipolar forming, thus, shows obvious switching characteristic (Fig 1b). Consequently, memory performance of surface treated device exhibits good endurance as compared to the as-deposited device (Fig 1c). The surface treated device demonstrates a stable switching with memory window (ON/OFF ratio) of about 7 times. This indicates that the thin oxidized layer at top electrode/ZnO interface plays a significant role in the device reliability. The defects concentration in the switching layer and the arrangement of the ionic conduction path may govern the formation and rupture of the conducting filament.3 Therefore, materials characterization and electrical conduction mechanism were conducted to explain the phenomena. This study offers a novel and simple method to enhance switching performance of the transparent resistive memory devices.