Low‐Voltage Flexible Copper Iodide Synaptic Transistors for Neuromorphic Computing

A flexible copper iodide (CuI) thin‐film transistor integrated with a chitosan gate dielectric is demonstrated in this article, which is fabricated on a polyethylene terephthalate (PET) substrate via a low‐temperature solution process. The device operation is enabled by the electric double layer effect induced by proton migration in chitosan, achieving low‐voltage driving at 2 V. Additionally, the device is tested under various mechanical bending conditions, demonstrating its flexibility and mechanical reliability. A transition from short‐term memory to long‐term memory is realized by modulating the pulse amplitude. Furthermore, the synaptic plasticity is shown to be tunable by pulse parameters (duration, frequency, number), which is quantitatively correlated with the proton diffusion kinetics in chitosan. These behaviors, resembling biological spike‐timing‐dependent plasticity, are systematically analyzed to establish a framework for neuromorphic computing. The results highlight the potential of the CuI/chitosan platform for flexible neuromorphic electronics, offering insights into adaptive learning rules and biohybrid systems.