Fabrication and Interfacial Charge Transfer of SnS/WSe2 van der Waals Heterostructures

초록

Two-dimensional van der Waals (vdW) heterostructures hold exceptional potential in optoelectronics, allowing us to harness the complementary properties of distinct materials while circumventing lattice mismatching limitations. The attainment of clean interface is critical in optimizing the performance of these heterostructures. In this study, we explore the growth mechanism of such heterostructures composed of mono- and dichalcogenide vdW layers, to gain insights into interface formation. Notably, we achieve these by directly growing tin sulfide (SnS) vdW crystals onto tungsten diselenide (WSe2) flakes through a two-step vapor transport method. Further, we investigate the influence of various synthetic parameters, including precursor concentration, substrate temperature, and carrier gas flow rate, on the quality of the resulting SnS/WSe2 heterostructures. These parameters critically influence the formation efficiency through mechanisms of selective deposition and epitaxial relationships. Ultimately, our findings pave the way for the precise engineering of band alignment and the advancement of enhanced optoelectronic properties within vdW heterostructures.