Details

Autor(en) / Beteiligte

• Momeni Pakdehi, Davood
• Schädlich, Philip
• Nguyen, Thi Thuy Nhung
• Zakharov, Alexei A.
• Wundrack, Stefan
• Najafidehaghani, Emad
• Speck, Florian
• Pierz, Klaus
• Seyller, Thomas
• Tegenkamp, Christoph
• Schumacher, Hans Werner

Titel

Silicon Carbide Stacking‐Order‐Induced Doping Variation in Epitaxial Graphene

Ist Teil von

• Advanced functional materials, 2020-11, Vol.30 (45), p.n/a

Ort / Verlag

Hoboken: Wiley Subscription Services, Inc

Erscheinungsjahr

2020

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• Generally, it is supposed that the Fermi level in epitaxial graphene is controlled by two effects: p‐type polarization doping induced by the bulk of the hexagonal silicon carbide (SiC)(0001) substrate and overcompensation by donor‐like states related to the buffer layer. The presented work is evidence that this effect is also related to the specific underlying SiC terrace. Here a periodic sequence of non‐identical SiC terraces is fabricated, which are unambiguously attributed to specific SiC surface terminations. A clear correlation between the SiC termination and the electronic graphene properties is experimentally observed and confirmed by various complementary surface‐sensitive methods. This correlation is attributed to a proximity effect of the SiC termination‐dependent polarization doping on the overlying graphene layer. These findings open a new approach for a nano‐scale doping‐engineering by the self‐patterning of epitaxial graphene and other 2D layers on dielectric polar substrates. For the first time, it is shown that there is a doping variation in epitaxial graphene, induced by a proximity effect of the underlying near‐surface silicon carbide (SiC) stacking order. This is enabled through advanced growth control, yielding pure monolayer graphene fabrication on non‐identical SiC terminations. This finding offers a novel growth‐mediated, doping‐engineering technique enabling advanced functionalization of graphene and stacking materials systems.