CMOS-Compatible Protonic Three-Terminal Memristor for Analog Synapse in Neuromorphic Computing.

Area of Science:

• Materials Science
• Electrical Engineering
• Computer Science

Background:

• All-solid-state inorganic hydrogen three-terminal memristors (H-3TMs) face challenges including poor retention, environmental sensitivity, and complex fabrication.
• Existing H-3TMs are not readily manufacturable using standard foundry processes, limiting their practical application.

Purpose of the Study:

• To develop a CMOS-compatible H-3TM that addresses the limitations of existing devices.
• To enable manufacturability within existing foundry processes and improve device performance.

Main Methods:

• Fabrication of a H-3TM using reversible proton intercalation between a SiNₓ electrolyte and WOₓ channel.
• Introduction of protons via hydrogen plasma treatment for CMOS compatibility and back-end-of-line integration.
• Experimental and simulation analysis of device characteristics, including retention, linearity, conductance states, energy consumption, and device-to-device variation.

Main Results:

• The developed H-3TM exhibits high retention performance due to low proton transport across the electrolyte/channel interface without an electric field.
• The device demonstrates linear potentiation/depression, 512 conductance states, a dynamic range of ≈40, and low energy operation (≈73 fJ per write).
• Excellent device-to-device uniformity was achieved, with analog properties evaluated on MNIST and Fashion-MNIST datasets, showing accuracies close to the ideal benchmark.

Conclusions:

• This work presents a viable CMOS-compatible H-3TM fabricated using a straightforward hydrogen plasma treatment.
• The device's robust performance and manufacturability offer a promising approach for designing and fabricating future artificial synaptic devices.
• The study highlights the potential of proton intercalation memristors for advanced computing applications.