Synaptic plasticity simulates behavior of low-voltage solution-processed Ag-doped CuI thin film transistors
Abstract
We demonstrate low-temperature solution-processed Ag-doped copper iodide (Ag-doped CuI) thin film transistors (TFTs) gated by chitosan dielectric for energy-efficient neuromorphic applications. Optimized at 8% Ag doping, the devices achieve a high current on/off ratio of 7.1 × 104, steep subthreshold swing (36.68 mV/dec), threshold voltage of 2.08 V, and saturation field-effect mobility of 2.43 cm2/V s. The electric double layer effect of chitosan enables low operating voltages by leveraging its frequency-dependent specific capacitance. Synaptic functionalities, including short-term plasticity, long-term plasticity, and paired-pulse facilitation (PPF), are emulated through proton migration dynamics in the chitosan dielectric, which induces a hysteresis window due to the slower proton transport rate compared to electron conduction in the channel. Systematic stability evaluations under negative bias stress, laser irradiation, and dynamic switching confirm robust operational reliability. The devices exhibit synaptic programmability, with PPF indices tunable via pulse intervals and amplitudes, mimicking biological learning rules. Combined with solution processability and low-temperature fabrication, these Ag-doped CuI TFTs address critical challenges in scalable neuromorphic hardware by integrating ionic-electronic coupling. This work establishes a materials strategy for brain-inspired computing, offering a pathway toward low-power adaptive electronics for portable biosensing and artificial neural networks.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (9)
Rui Xiang
School of Physics and Electronics, Key Laboratory for Multifunctional Ionic Electronic Materials and Devices of Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Key Laboratory of Physics and Devices in Post-Moore Era, College of Hunan Province, Hunan Normal University , Changsha 410081,
Wei Dou
Junting Liu
Sunwen Liu
School of Physics and Electronics, Key Laboratory for Multifunctional Ionic Electronic Materials and Devices of Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Key Laboratory of Physics and Devices in Post-Moore Era, College of Hunan Province, Hunan Normal University , Changsha 410081,
Xiaodong Xu
Pengfei Chen
State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering
Yuling Peng
School of Physics and Electronics, Key Laboratory for Multifunctional Ionic Electronic Materials and Devices of Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Key Laboratory of Physics and Devices in Post-Moore Era, College of Hunan Province, Hunan Normal University , Changsha 410081,
Weichang Zhou
School of Physics and Electronics, Hunan Normal University 3 , Changsha 410081,
Dongsheng Tang
Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, Key Laboratory for Multifunctional Ionic Electronic Materials and Devices, College of Physics and Electronics, Hunan Normal University , Changsha 410081, Hunan,