▎ 摘 要
Van der Waals epitaxy growth of two-dimensional materials promise controllable fabrication of novel artificial heterostructures. Here, we report molecular beam epitaxy growth of continuous molybdenum ditelluride (MoTe2) films on graphene substrates with good stoichiometry in both 2H and 1T' phases. Post-growth annealing reveal phase transition suppressed in Te-rich atmosphere, through in-situ scanning tunneling microscopy/spectroscopy and X-ray photoelectron spectroscopy. Our results suggest a new route to fabricate atomically ultrathin MoTe2 lateral heterophase homojunctions, showing potential applications in future lateral thin-film transistors. (C) 2017 Elsevier Ltd. All rights reserved.