Two-dimensional materials Transition Metal Dichalcogenides (TMDs) are a novel type of semiconductor material with tunable bandgap and atomic-level thickness. Different TMDs can be flexibly combined to form heterostructures with distinct properties. In this paper, we have prepared two-dimensional MoSe/WSe vertical and lateral heterostructures by using CVD and a combination of PVD and CVD, respectively. Subsequently, the structure, electronic and optoelectronic properties of these two types of heterostructures were characterized. The results indicate that field-effect transistors based on single-layer MoSe/WSe lateral heterostructures, and single-layer WSe/multi-layer MoSe and single-layer MoSe/multi-layer WSe vertical heterostructures exhibit significant rectification effects. The in-plane monolayer MoSe/WSe heterostructure devices exhibit the on/ff ratio of up to 10, and the monolayer-multilayer vertical heterostructure reaching 10, significantly outperforming most known devices of the same type. Moreover, the optical response of both in-plane and vertical heterostructures field-effect transistors reach 10 ms. Our research findings offer pathways for the flexible selective growth of in-plane and vertical heterostructures based on TMDs, and provide insights into achieving diverse performance in logic devices.

中文翻译：

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二维MoSe2/WSe2横向和垂直异质结构的制备及其光电性能

二维材料过渡金属二硫化物（TMD）是一种具有可调谐带隙和原子级厚度的新型半导体材料。不同的TMD可以灵活组合形成具有不同性质的异质结构。在本文中，我们分别使用CVD以及PVD和CVD相结合制备了二维MoSe/WSe垂直和横向异质结构。随后，对这两类异质结构的结构、电子和光电性质进行了表征。结果表明，基于单层MoSe/WSe横向异质结构、单层WSe/多层MoSe和单层MoSe/多层WSe垂直异质结构的场效应晶体管表现出显着的整流效应。面内单层MoSe/WSe异质结构器件的开/关比高达10，单层-多层垂直异质结构达到10，明显优于大多数已知的同类型器件。此外，面内和垂直异质结构场效应晶体管的光学响应均达到10 ms。我们的研究结果为基于 TMD 的面内和垂直异质结构的灵活选择性生长提供了途径，并为实现逻辑器件的多样化性能提供了见解。