Ion-Doped Polyvinyl Alcohol (PVA)-Based Thin-Film Transistor for Logic Electronics and Neuronal Synapse

Low-power biodegradable artificial synaptic devices are one of the important directions for future neuromorphic computing development, and synaptic transistors based on polymer materials open a new path to green electronics. Polyvinyl alcohol (PVA), as a polymer material with electrical double layer effect, is a potential dielectric in artificial synaptic transistors. However, the low ionic conductivity of PVA is a block for its application. Here, we raised the augmentation of the capacitance of PVA through ion doping. Based on ion-doped PVA dielectric, synaptic transistor shows excellent performance, including low subthreshold swing (SS) of 0.13 V/decade and high $\textit{I}_{\text{on}}$ / $\textit{I}_{\text{off}}$ of 3.5 $\times$ 10 $^{\text{6}}$ . Based on this transistor, a resistor-loaded inverter is constructed, which has full swing characteristics and high voltage gain. In addition, activity dependent synaptic responses, such as excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), and high-pass filtering, are vividly imitated in a single synaptic device. Furthermore, fabricated device can be dissolved in water easily. The proposed synaptic transistor is a candidate in future "green" low-power devices.