posted on 2024-01-29, 13:08authored byHyun Jeong, Komla Nomenyo, Hye Min Oh, Agnieszka Gwiazda, Seok Joon Yun, Clotaire Chevalier César, Rafael Salas-Montiel, Sibiri Wourè-Nadiri Bayor, Mun Seok Jeong, Young Hee Lee, Gilles Lérondel
Two-dimensional transition-metal
dichalcogenides have attracted
significant attention because of their unique intrinsic properties,
such as high transparency, good flexibility, atomically thin structure,
and predictable electron transport. However, the current state of
device performance in monolayer transition-metal dichalcogenide-based
optoelectronics is far from commercialization, because of its substantial
strain on the heterogeneous planar substrate and its robust metal
deposition, which causes crystalline damage. In this study, we show
that strain-relaxed and undamaged monolayer WSe2 can improve
a device performance significantly. We propose here an original point-cell-type
photodetector. The device consists in a monolayer of an absorbing
TMD (i.e., WSe2) simply deposited on a structured electrode,
i.e., core–shell silicon–gold nanopillars. The maximum
photoresponsivity of the device is found to be 23.16 A/W, which is
a significantly high value for monolayer WSe2-based photodetectors.
Such point-cell photodetectors can resolve the critical issues of
2D materials, leading to tremendous improvements in device performance.