Bi₂O₂Se-based CBRAM integrated artificial synapse

Area of Science:

• Materials Science
• Nanotechnology
• Electronics

Background:

• Two-dimensional (2D) semiconducting materials are crucial for advanced memory applications.
• Bismuth oxyselenide (Bi₂O₂Se) is a 2D material with high electron mobility and significant potential.
• Memristor structures integrating 2D materials enable novel memory devices.

Purpose of the Study:

• To investigate the out-of-plane switching behavior of few-layered Bi₂O₂Se.
• To explore its application in conductive bridge random access memory (CBRAM).
• To evaluate its potential as an artificial synapse for neuromorphic computing.

Main Methods:

• Fabrication of a CBRAM device using CVD-grown Bi₂O₂Se as the switching material (SM) in an Al/Cu/Bi₂O₂Se/Pd structure.
• Characterization of device performance, including DC cycling, voltage retention, and multilevel switching.
• Analysis of the switching mechanism using High-Resolution Transmission Electron Microscopy (HRTEM).

Main Results:

• The CBRAM device demonstrated approximately 90 stable DC switching cycles with consistent SET/RESET voltages.
• Excellent data retention exceeding 10 ks was observed.
• Multilevel switching characteristics were achieved, showing four distinct states.
• Successful realization of an artificial synapse with tunable potentiation and depression.

Conclusions:

• Few-layered Bi₂O₂Se exhibits intrinsic switching behavior suitable for CBRAM applications.
• The material shows potential for use in artificial synapses for neuromorphic computing.
• Cu migration through Bi₂O₂Se is identified as the switching mechanism.
• The developed structure holds promise for future integrated memory technologies.