Heterosynaptic Memtransistors Based on Switching Operation Mechanism Using Designed Organic/Inorganic Heterostructures for Neuromorphic Electronics

ABSTRACT Memtransistors using low‐dimensional semiconductors represent a promising gate‐tunable heterosynaptic architecture for neuromorphic computing. However, active layers of these devices have not yet been artificially designed or controlled. In this study, gate‐pulse‐tunable heterosynaptic neuromodulation is achieved using memtransistors with organic semiconductor tris(4‐carbazoyl‐9‐ylphenyl)amine (TCTA)/MoS ₂ heterostructures designed via energy‐band engineering and bottom‐contact architecture. Memristive switching is realized through distinctive low‐ and high‐conduction states with a switching ratio of 10 ² , modulated by gate pulses. As the gate voltage ( V _G ) decreases from +30 to −30 V, the memristive hysteresis for the bottom contact TCTA/MoS ₂ FET without post‐treatment and an h‐BN insulating layer appears at V _G = −15 V and broadens with an increasing switching ratio. Intriguingly, as V _G becomes increasingly negative ( V _G < −15 V), trap‐related space‐charge‐limited conduction becomes dominant. Non‐volatile heterosynaptic behavior is mimicked by drain pulses and modulated by gate‐pulse polarities. Applying gate‐pulse only, analogous responses are observed in synaptic modulation with time constants of 100 ms for potentiation and 60 ms for depression. The design of multi‐functional memory and realization of gate‐pulse‐tunable memtransistors using nanoscale TCTA/MoS ₂ can promote energy‐efficient, tunable, and reliable heterosynaptic neuromorphic electronics.