Chemical vapor deposited WS₂/MoS₂ heterostructure photodetector with enhanced photoresponsivity

Abstract

Two-dimensional transition metal chalcogenides (TMDCs) have attracted great interest due to their unique semiconductor properties. Among all TMDC materials, MoS2 and WS2 are promising for composing heterostructures. However, traditional TMDC heterostructure fabrication depends on transfer process, with drawbacks of interface impurity and small size. In this work, a two-step chemical vapor deposition (CVD) process was applied to synthesize large-scale WS2/MoS2 heterostructure. Surface morphology and crystal structure characterizations demonstrate the high-quality WS2/MoS2 heterostructure. The WS2/MoS2 heterostructure photodetector fabricated by photolithography exhibits an enhanced photoresponsivity up to 370 A W-1 in comparison with single WS2 or MoS2 devices. This study suggests a direct CVD growth of large-scale TMDC heterostructure films with clean interface. The built-in electric field at interface contributes to the separation of photo-generated electron-hole pairs, leading to enhanced photocurrent and responsivity, and showing promising potentials in photo-electric applications.

Exciton dynamics and photoresponse of a CVD-grown WS2/thermally evaporated CsSnBr3 heterostructure

“…2(e), which was apparently longer compared to those reported elsewhere. 17,37,38 The formation of the larger area WS 2 domains not only indicated the effective tuning of the CVD process, but also benefited the further perovskite deposition and photodetector fabrication. The thickness of the WS 2 domain was also measured via AFM, as shown in the inset of Fig.…”

“…It could be found that the monolayer WS 2 and CsSnBr 3 isolated layer revealed PL emissions at 640 and 670 nm, respectively, which were consistent with those reported in the literature. 28,29,37,41 After 10 nm CsSnBr 3 deposition, the WS 2 /CsSnBr 3 heterostructure exhibited both WS 2 and CsSnBr 3 PL emission, with an intensity ratio of 0.455 for I CsSnBr 3 /I WS 2 . With the increase in the thickness of CsSnBr 3 to 50 nm, the PL emission ratio of I CsSnBr 3 /I WS 2 is almost equal.…”

Research progress of transition-metal dichalcogenides for the hydrogen evolution reaction

“…136,137 Additionally, molecular beam epitaxy and transfer techniques can also achieve the alternate stacking of different materials. 138,139…”

“…To attain superior results by fostering coordinated interactions among diverse components Prepared directly 136,137 There is a wide variety of heterogeneous structure combinations Molecular beam epitaxy 138 Transfer techniques 139…”