p⁺-Si/n-ZnO/Ni Heterojunction OptoelectronicSynaptic Device for Visual Memory

Artificial visual memory systems based on optoelectronic synaptic device are receiving a lot of renewed attention due to their ability to combine the advantages of both photonics and electronics for image recognition and integrated sensing, cognitive tasks, and more. In this work, the electric field-tunable and light-tunable synaptic memory behaviors have been demonstrated based on p(+)-Si/n-ZnO heterostructure. The electron trapping and detrapping tuning mechanisms at the p(+)-Si/n-ZnO interface have been presented to explain the memory properties by the stimulation of electric field and light irradiation. Thus, the p(+)n heterojunction optoelectronic synaptic device provides the function of detecting and storing different light information, realizing short-term memory (STM)/long-term memory (LTM) and "learning-experience" behaviors for the light information. Furthermore, the optoelectronic synaptic array system has been built to achieve the detection and storage processes of pattern-specific light information, indicating its potential applications in the artificial visual memories