Flexible synaptic floating gate devices with dual electrical modulation based on ambipolar black phosphorus

Area of Science:

• Materials Science
• Nanotechnology
• Neuromorphic Engineering

Background:

• Two-dimensional van der Waals materials are promising for synaptic devices in intelligent computing.
• Robust flexible synaptic transistors are crucial for soft robotics and wearable applications but are under-researched.

Purpose of the Study:

• To demonstrate a flexible synaptic device using black phosphorus with dual working modes.
• To evaluate its performance for energy-efficient computation and mechanical robustness.

Main Methods:

• Fabrication of a floating gate synaptic transistor on a flexible substrate using ambipolar black phosphorus.
• Characterization of device performance in three-terminal (nonvolatile) and two-terminal (quasi-nonvolatile) modes.
• Assessment of endurance under repeated bending cycles.

Main Results:

• The device exhibited nonvolatile and quasi-nonvolatile memory effects in its respective modes.
• The three-terminal mode achieved energy-efficient computation with sub-fJ/spike energy consumption and fast response (~10 ns).
• The flexible device showed good endurance with 5,000 bending cycles at ~0.63% strain.

Conclusions:

• The demonstrated flexible black phosphorus synaptic device offers a viable platform for low-power neuromorphic applications.
• Its dual working modes and mechanical flexibility are suitable for advanced wearable and robotic systems.
• This work advances the development of next-generation intelligent and energy-efficient electronic systems.