Capacitive-Coupled-Plasma-Assisted Technique for Optoelectronic Synaptic Devices with a Wide Spectral Response

This study presents a single-step capacitive-coupled-plasma-assisted sputtering technique that enables simultaneous material deposition and in situ plasma treatment. This integrated approach enhances persistent photoconductivity and broadens the spectral response in InGaZnO-based optoelectronic synaptic devices. The resulting plasma-assisted InGaZnO exhibits a narrow gap, high disorder, increased oxygen vacancies, and a smooth surface. This technique enables the device to perceive and memorize ultraviolet-to-visible light, thereby improving synaptic plasticity with a maximum relaxation time of 129.41 s, a paired-pulse facilitation index of 216.40%, and an A20/A1 gain index of 3232.51%, surpassing the baseline device by factors of 706.67, 1.96, and 13.06, respectively.