Regensburg 2022 – wissenschaftliches Programm
O 65.3: Vortrag
Donnerstag, 8. September 2022, 11:00–11:15, S052
On the transition from MoS2 single-layer to bilayer growth on the Au(111) surface — •Moritz Ewert1, Lars Buß1, Francesca Genuzio3, Tevfik Onur Menteş3, Andrea Locatelli3, Jens Falta2, and Jan Ingo Flege1 — 1Applied Physics and Semiconductor Spectroscopy, Brandenburg University of Technology Cottbus-Senftenberg, Germany — 2Institute of Solid State Physics, University of Bremen, Germany — 3Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, Italy
MoS2 is well known for changing from an indirect to a direct band-gap semiconductor as a single layer. Here, for the model system MoS2/Au(111), we present in-situ studies of the continued growth of micron-size single-layer MoS2 islands including the first formation of bilayer patches.
We have used angle-resolved photoemission spectroscopy from micrometer sized regions to investigate the local band structure of the islands’ rims and centers, showing a prevalence for bilayer and single-layer formation at the rims and centers, respectively. The bilayer patches can clearly be identified locally on the few nanometer scale employing intensity-voltage low-energy electron microscopy as a fingerprinting method. Astonishingly, micro-spot low-energy electron diffraction hints toward the nucleation of the second layer of the MoS2 between the single layer MoS2 and the Au(111) substrate when the step bunches formed by the single-terrace growth mechanism become sufficiently high.