Improved Resistive Switching Observed in Ti/Zr₃N₂/p-Si Capacitor via Hydrogen Passivation

Abstract

Charge-trap based resistive switching (RS) has attracted attention in the resistive random-access memory (RRAM) industry due to its gradual RS behavior for multi-level and synaptic applications. In this work, in order to lower the operating current level closely related to device's degradation, we applied a hydrogen passivation to Zr 3 N 2 based RRAM devices and investigated the correlation between current level and trap density, such as an interface trap density (N it ) at the Zr 3 N 2 /p-Si layer and nitride trap density (N nt ) within Zr 3 N 2 films, for memory cells annealed in conventional N 2 gas as well as H 2 gas. Compared to the N 2 -annealed sample, after H 2 annealing, N it is lowered by the hydrogen passivation effect, which results in a reduction of both current level at high resistive state (HRS) and variation of HRS and low resistive state (LRS). As a result, in the H 2 annealed Zr 3 N 2 RRAM cell, we observed a lower operation voltage/current, longer endurance, and larger read margin due to the hydrogen passivation effect.INDEX TERMS Hydrogen passivation, rapid thermal annealing, resistive switching, self-rectifying, Zr 3 N 2 , nitride trap density, interface trap density.

Effect of Hydrogen Annealing on Performances of BN-Based RRAM

“…However, the presence of defects and impurities in the material can lead to unwanted leakage currents, which can reduce the on/off ratio of the device. The hydrogen annealing process can help reduce the number of defects in BN-based RRAM, which can reduce leakage currents and increase the on/off ratio of the device, which is consistent with other papers [ 24 , 29 ].…”

“…Hydrogen annealing has been proposed as a promising technique to mitigate these issues. Hydrogen annealing involves exposing a material to hydrogen gas at high temperatures to react with dangling bonds or other defects, which can passivate bulk traps, and interface traps, and thereby improve the electrical properties of the material [ 24 , 25 ]. Hydrogen annealing is believed to improve the stability of RRAM devices by passivating defects in the metal oxide layer.…”

Self-Rectifying Gr/TMDC Heterostructures: Candidates for Resistive Switching Memory Devices

“…Conventional memory storage devices, such as flash memory, are approaching their limit in time to come. Recently, resistance-dependent novel memories, including magnetic random-access memory (MRAM), phase-change random access memory (PRAM), and resistive switching-based random-access memory (RRAM), have gained popularity in place of conventional three-terminal charge-based memory devices due to their dominant, simplistic 2-terminal structure, and broad device integration rate. − Among them, RRAM devices attract researchers because of their simple metal–insulator–metal (MIM) and metal–insulator–semiconductor (MIS) structures with nonvolatile nature, excellent endurance stability (>10 3 ), fast switching response (<10 ns ), and a long retention time (>10 3 s). − As the integration scale continues to minimize, the density of devices can be increased on a smaller area and exhibit much better performance by utilizing multiple active cells. It can be achieved by fabricating a vertically stacked crossbar arrangement structure, which increases the memory storage density to a larger extent.…”