Array-level MXene electrode flexible long-term-plasticity synaptic transistors

Artificial nervous devices are expected to emulate the information processing methods of the human brain to achieve high-speed low-power computing. In these systems, synaptic transistors mimic the brain's input and storage mechanisms in response to external stimuli. Achieving a high-integration flexible synaptic transistor array with long-term plasticity and mass-production potential remains difficult due to structural and material limitations. In this work, novel array-level MXene-electrode flexible synaptic transistors have been realized with a long-term synaptic plasticity of over 1000 s without requiring a floating gate structure, electrolyte dielectrics, or ferroelectric materials. The Ti₃C₂T_x MXene electrodes provide protons from surface functional groups to fill the defects of the dielectric layer to achieve long-term synaptic plasticity. Furthermore, the method of patterning MXene electrodes enables both a high level of integration and array-level patterning, which had been highly challenging, especially on flexible substrates. Additionally, the matched work functions of MXene and semiconducting carbon nanotubes enable Ohmic contact for the metal-semiconductor junction. Furthermore, an MXene electrode flexible synaptic transistor (MEFST) array is made possible for next-generation 3D perception systems to achieve artificial neuromorphic computing and temporal fusion information storage based on long-term plasticity, leading to a high accuracy of 93.8% for recognising handwritten digits. Long-term plasticity allows rapid identification upon the reappearance of the same target without needing re-iteration. The MEFST array holds immense application potential for neuromorphic electronic skin, intelligent wearable electronics and edge computing.