Exploring response time and synaptic plasticity in P3HT ion-gated transistors for neuromorphic computing: impact of P3HT molecular weight and film thickness

Abstract

Neuromorphic computers, inspired by the brain's neural networks, hold promise for efficient computation. Ion-gated transistors (IGTs), which employ ionic gating media, are particularly attractive for use in neuromorphic computing with remarkably low power consumption. This study focuses on IGTs utilizing organic polymer films of poly (3-hexylthiophene) (P3HT) as synaptic elements. The impact of P3HT molecular weight (MW, i.e. 24 kDa, 42 kDa, 92 kDa) and P3HT film thickness on IGT response time and synaptic behavior is investigated. Various synaptic behaviors are emulated, including paired-pulse facilitation (PPF) and spike number-dependent plasticity (SNDP). Additionally, the transition from short-term plasticity (STP) to long-term plasticity (LTP) is achieved by tuning MW, channel thickness, and gate-source voltage (V_gs) pulse parameters. These findings pave the way for P3HT-based IGTs as advanced artificial synaptic elements for neuromorphic computing.