Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 89: Metal and Semiconductor Substrates: Structure, Epitaxy and Growth

O 89.8: Vortrag

Donnerstag, 20. März 2025, 16:45–17:00, H8

Strong electron doping of single-layer MoS₂ on an oxidized contact — •Marco Bianchi^1,2, Charlotte Sanders³, Davide Curcio⁴, Daniel Lizzit⁵, Paolo Lacovig¹, Ezequiel Tosi⁶, Jill Miwa², Silvano Lizzit¹, and Philip Hofmann² — ¹Elettra Sincrotrone Trieste S.C.p.A., Trieste, IT — ²Dep. of Physics and Astronomy, iNANO, Aarhus University, DK. — ³Artemis Program, UK Central Laser Facility, Harwell, STFC, UK — ⁴IOM, Consiglio Nazionale della Ricerca, Trieste, IT — ⁵DPIA - University of Udine, IT — ⁶Instituto de Ciencia de Materiales de Madrid (ICMM - CSIC), ES

One of the major obstacles for the use of two-dimensional semiconductors in devices continues to be the high contact resistance to metallic conductors and the associated losses. Promising results have recently been obtained by using group V semimetals as contact materials. The obtained low contact resistance was explained partly by the a degenerate doping of the two-dimensional semiconductor. Here we study the band alignment and structure of such a system, a single-layer of MoS₂ on Au(111) with an intercalated layer of Bi. We investigate the electronic structure and growth by angle-resolved photoemission spectroscopy, X-ray photoemission spectroscopy, low energy electron diffraction and scanning tunneling microscopy. Our results show no evidence for an occupation of the MoS₂ conduction band when the material is brought into close contact with Bi. Surprisingly, however, a subsequent oxidation of the intercalated Bi gives rise to an extremely strong electron doping of the conduction band with a carrier density on the order of 10¹³ cm⁻².

Keywords: TMDC; MoS2; Bismuth oxide; Electronic properties