Correlation between resistive switching characteristics and density of traps observed in Zr3N2 resistive switching memory devices with TiN barrier electrode

Abstract

In this study, we present a correlation between the resistive switching (RS) characteristics and the traps of Zr3N2, which is based resistive random-access memory (RRAM) with a TiN barrier electrode, in order to identify the RS mechanism of the trap-based RRAM devices. First, gradual asymmetrical RS properties were discovered in the RS test, which included a current ratio of >2.51 × 102 and a large read margin of 480. As a result of analyzing the trap, the RS characteristics were deeply related to the nitride trap density (Nnt) in the Zr3N2 films as opposed to the interface trap density (Nit) at Zr3N2/p-Si layer. In addition, in the trap evaluation for four different resistance states, we observed that the Nnt was consistently increased with a decreasing resistance. These results indicate that the resistance state of the proposed TiN/Zr3N2/p-Si memory cell is determined by the Nnt, which means that controlling the Nnt is important in order to achieve a stable resistance state.