摘要
Two-dimensional(2D)graphene has emerged as an excellent partner for solving the scarcity of ultraviolet photodetectors based on three-dimensional(3D)AlGaN,in which the design of a 2D graphene/3D AlGaN junction becomes crucial.This study investigates the response mechanisms of two distinct graphene/AlGaN(Gr-AlGaN)photodetectors in the lateral and vertical configurations.For the lateral Gr-AlGaN photodetector,photogenerated electrons drifting into p-type graphene channel induce negative photoconductivity and a persistent photoconductive effect,resulting in a high responsivity of 1.27×10^(4) A∕W and detectivity of 3.88×10^(12) Jones.Although the response capability of a vertical Gr-AlGaN device is inferior to the lateral one,it shows significantly reduced dark current and self-powered detection.The photogenerated electron-hole pair can be spontaneously separated by the junction electric field and generate a photocurrent at zero bias.Hence,the vertical Gr-AlGaN photodetector array is satisfied for passive driving imaging like deep space detection.Conversely,the exceptional response of the lateral Gr-AlGaN device emphasizes its prospects for steady object recognition with low-light emission.Moreover,the improved imaging sharpness with light illumination duration makes it suitable for biomimetic visual learning,which follows a recognition to memory process.This study elucidates an efficient approach for diverse photodetection applications through the configuration design of Gr-AlGaN junctions.
基金
Natural Science Foundation of Jilin Province(20230101107JC,20230101345JC,20230508132RC)
Science and Technology Research Project of Education Department of Jilin Province(JJKH20230183KJ)
National Natural Science Foundation of China(61827813,62074147,62121005,62374165)
Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)
General Project from Jilin University of Finance and Economics.
