GeO 2 /SiO 2 /p‐Si Heterojunction Optoelectronic Memristors: A Multifunctional Platform for Solar‐Blind UV Detection and Neuromorphic Recognition

Abstract

Optoelectronic memristors with sensing, storage, and computing multifunctional applications are promising for efficient in‐memory computing and intelligent visual perception. However, it is still a huge challenge to integrate these functions in a single optoelectronic platform due to the inherent contradiction between the volatile photoresponse of photodetectors and the persistent photoconductivity of memristors. Here, multifunctional optoelectronic memristors (MOMs) based on vertical GeO 2 /SiO 2 /p‐Si heterojunctions have been successfully developed with the integration of 213‐nm solar‐blind UV photodetection and artificial synaptic functionality. The GeO 2 MOM exhibits an ultralow dark current of 3 pA and a photo‐dark current ratio over 10 3 in self‐powered mode, and decreases in fast rise and decay times by more than 40‐fold and 13‐fold at an applied bias voltage of −0.7 V, enabling solar‐blind optical communication and reconfigurable optoelectronic logic gate applications. Moreover, it demonstrates stable bipolar resistive switching with a high‐to‐low resistance ratio exceeding 35 under electric field stimulation and emulates five‐dimensional synaptic plasticity under optical pulse stimulation, with which handwritten digit image recognition has been realized with a high accuracy of 96.98%. This work designs an excellent multifunctional platform and provides a versatile strategy for the development of high‐performance GeO 2 optoelectronic devices.