Pan, Y.Fölsch, S.Lin, Y. -CJariwala, B.Robinson, J. A.Nie, YifanCho, KyeongjiaeFeenstra, R. M.2020-02-252020-02-252019-01-172053-1583http://dx.doi.org/10.1088/2053-1583/aaf58chttps://hdl.handle.net/10735.1/7298Due to copyright restrictions and/or publisher's policy full text access from Treasures at UT Dallas is limited to current UTD affiliates (use the provided Link to Article).Supplementary material is available on publisher's website.Scanning tunneling microscopy (STM) at 5 K is used to study WSe₂ layers grown on epitaxial graphene which is formed on Si-terminated SiC(0 0 0 1). Specifically, a partial hydrogenation process is applied to intercalate hydrogen at the SiC-graphene interface, yielding areas of quasi-free-standing bilayer graphene coexisting with bare monolayer graphene. We find that an abrupt and structurally perfect homojunction (band-edge offset ∼0.25 eV) is formed when WSe₂ overgrows a lateral junction between adjacent monolayer and quasi-free-standing bilayer areas in the graphene. The band structure modulation in the WSe₂ overlayer arises from the varying work function (electrostatic potential) of the graphene beneath. Scanning tunneling spectroscopy measurements reveal that this effect can be also utilized to create WSe₂ quantum dots that confine either valence or conduction band states, in agreement with first-principles band structure calculations. ©2019 IOP Publishing Ltd.en©2019 IOP Publishing Ltd.GrapheneHydrogenationMonomolecular filmsNanocrystalsScanning tunneling microscopySelenium compoundsQuantum dotsSilicon carbideElectrostaticsTungsten compoundsarticlePan, Y., S. Fölsch, Y. -C Lin, B. Jariwala, et al. 2019. "WSe 2 homojunctions and quantum dots created by patterned hydrogenation of epitaxial graphene substrates." 2d Materials 6(2): art. 021001, doi: 10.1088/2053-1583/aaf58c62