Fabrication of Lattice-Mismatched MoTe2/MoSe2 Heterostructures using Molecular-Beam Epitaxy

We have fabricated a heterostructure consisting of alternately stacked MoSe2 and MoTe2 monolayers (MLs) using molecular beam epitaxy. With the aid of weak van der Waals interactions between adjacent MLs, heterostructures as thick as six MLs were grown, despite the large lattice mismatch (−6.51%) between MoSe2 and MoTe2. The large lattice mismatch, on the other hand, promotes the formation of slightly twisted epitaxial domains, which increases the angular distribution in the epitaxial orientations as the film thickness is increased.