Electrical Characteristics of CdSe Quantum Dot Floating Gate Devices for Neuromorphic Synaptic Memory Applications

Flash memory-based synaptic devices are promising components for neuromorphic computing due to their non-volatility and analog programmability. In this study, CdSe/ZnS quantum dots (QDs) were employed as floating gate materials to enhance the performance of conventional flash memory structures. Pt/Cr/Al₂O₃/QDs/Al₂O₃/SiO₂/Si stacked capacitors and floating gate transistors (FGTs) were fabricated, and their electrical characteristics were investigated. Capacitance–voltage (C–V) measurements revealed a memory window exceeding 2 V, confirming effective charge storage. The fabricated CdSe/ZnS QD-based FGT exhibited threshold voltage shifts in transfer curves, demonstrating analog synaptic weight modulation. The capacitor device showed reliable charge trapping behavior and stable data retention under repeated program/erase (P/E) cycling. P/E characteristics of the FGT were also examined, showing consistent switching suitable for neuromorphic applications. These results confirm the feasibility of CdSe/ZnS QD-based floating gate devices as high-performance non-volatile memory elements and artificial synapses for energy-efficient neuromorphic computing systems.