▎ 摘　　要

Here, we have fabricated high-performance near-infrared (NIR) tunnelling heterojunction photodetectors (THPDs) by in-situ synthesizing three-dimensional (3D) grapheneon Si with the insertion of a high-kappa tunnelling layer. Combining the high light-harvesting ability of 3D-graphene and the effective dark current suppression of the high-kappa tunnelling layer, the trade-off between the ultrafast response and ultra-sensitivity in graphene-based PDs is successfully bridged. Our device exhibits ultra-high responsivity (11.2 A/W), excellent specific detectivity (5.9 x10(10) Jones), and ultra-fast response(168 mu s) at the communication wavelength (1550 nm). This work provides a universal strategy to fabricate high-performance and low-cost graphene/silicon PDs in the communication wavelength.