Epitaxial growth of bilayer MoS2/MoSe2 heterostructure with high-responsivity enhanced by photogating effect

Van der Waals (vdW) semiconductors heterostructure based on transition metal dichalcogenides (TMDs) is a promising candidate for two-dimensional (2D) ultra-thin optoelectronic devices due to the strongly interlayer coupling and efficient carrier separation. However, the directly epitaxial growth of 2D TMDs vdW heterostructures with a clean interface and high photoresponsivity still remains a challenging. In this work, the epitaxial growth of bilayer MoS2/MoSe2 vdW heterostructure with atomic-layer clean interface is prepared via an iodine-assisted growth strategy. The electrical properties and optoelectronic characterization proves that the heterostructure device presents an enhanced photoresponsivity of 680 A/W, indicting the 21.25 times higher compared with pure MoS2, which benefited from the photogating effect formed by the localized electrons in this heterostructure. This study offers a well reference for the controlled growth of the TMDs vdW heterostructure, and the achieved heterostructure will prove promising applications in future integrated optoelectronic devices and systems.

Automated summary

In this study, a bilayer MoS2/MoSe2 vdW heterostructure with an atomic-layer clean interface was successfully prepared using an iodine-assisted growth strategy, and it was shown to exhibit enhanced photoresponsivity. This study provides an important reference for the controlled growth of TMDs vdW heterostructures.