Room-temperature processable amorphous Ga2O3 synaptic transistor for solar-blind ultraviolet perception

Gallium oxide (Ga 2 O 3 )-based optoelectronic synapses are promising for solar-blind neuromorphic perception, yet their practical applications is currently hindered by energy consumption issues and the high fabrication temperature commonly required for crystalline devices. Herein, a room-temperature processable amorphous Ga 2 O 3 synaptic transistor is developed to simultaneously achieve deep-ultraviolet photodetection and optoelectronic synaptic plasticity. Under 254 nm illumination, the device exhibits a photo-to-dark current ratio of 3.32 × 10 7 , a responsivity of 8.9 × 10 3 A·W −1 , and a detectivity of 1.96 × 10 17 Jones. These key parameters are comparable to those of crystalline Ga 2 O 3 photodetectors. The transistor further emulates essential synaptic behaviors, including short-term memory, long-term memory, paired-pulse facilitation, and learning-forgetting-relearning behaviors, together with an ultralow energy consumption of 127.42 fJ per pulse. Benefiting from the intrinsic solar-blind response and defect-assisted persistent photoconductivity of a-Ga 2 O 3 , the device enables graded UV warning perception and sensitization response emulation. In addition, the experimentally obtained synaptic dynamics are used to demonstrate the potential of the device for temporal information processing in a reservoir-computing framework. This work establishes room-temperature amorphous Ga 2 O 3 as a promising platform for low-energy solar-blind optoelectronic synapses and bio-inspired ultraviolet perception.