Understanding the Origin of Unreliable Low-Resistance State During Initialization Process

The main factor hindering the massive employment for resistive random access memory (RRAM) can be ascribed to reliability issues. It has been reported that resistive switching (RS) characteristics were unstable during initial
${I}-{V}$
cycles; however, the reason has not been studied yet. In this article, the mechanism for a significant increase in a low-resistance state (LRS) value during the initial cycles has been investigated. In this article, we suggest that the initialization process is actually the formation process of a stable TaOx interface layer between the RS layer and the top electrode (TE). Furthermore, a co-regulation model of the filament-type and the interface-type switching mechanisms on RS behavior is proposed, which explains the complete working process of devices. By reducing the size of the device and increasing the positive stop voltage, the initialization process of the device has been greatly shortened. This article may promote the development of advanced and reliable RRAM devices.