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

authored by: Davood Momeni Pakdehi, Philip Schädlich, Thi Thuy Nhung Nguyen, Alexei A. Zakharov, Stefan Wundrack, Emad Najafidehaghani, Florian Speck, Klaus Pierz, Thomas Seyller, Christoph Tegenkamp, Hans Werner Schumacher
Abstract: 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.
External Organisation(s): National Metrology Institute of Germany (PTB)
Chemnitz University of Technology (CUT)
MAX-lab
Type: Article
Journal: Advanced functional materials
Volume: 30
ISSN: 1616-301X
Publication date: 04.11.2020
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Chemistry(all), Materials Science(all), Condensed Matter Physics
Electronic version(s): https://doi.org/10.1002/adfm.202004695 (Access: Open)

BibTeX

@article{e0277a4414d7482c8ed79f27a2c3f0c4,
title = "Silicon Carbide Stacking-Order-Induced Doping Variation in Epitaxial Graphene",
abstract = "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.",
keywords = "epitaxial graphenes, hexagonal silicon carbides, SiC spontaneous polarization, surface-dependent polarization doping",
author = "{Momeni Pakdehi}, Davood and Philip Sch{\"a}dlich and Nguyen, {Thi Thuy Nhung} and Zakharov, {Alexei A.} and Stefan Wundrack and Emad Najafidehaghani and Florian Speck and Klaus Pierz and Thomas Seyller and Christoph Tegenkamp and Schumacher, {Hans Werner}",
note = "Funding information: [ The authors gratefully acknowledge M. Wenderoth and A. Sinterhauf for valuable discussions. This work was supported in part by the Joint Research Project “GIQS” (18SIB07). This project received funding from the European Metrology Programme for Innovation and Research (EMPIR) co?financed by the Participating States and from the European Unions{\textquoteright} Horizon 2020 research and innovation programme. A.A.Z. acknowledges the support from Stiftelsen f{\"o}r Strategisk Forskning (project RMA15?0024). The authors thank DFG Project Te386/12?1 for their support. The authors also acknowledge the funding from the European Commission Graphene Flagship Core2 (grant agreement 785219). The work was co?funded by the Deutsche Forschungsgemeinschaft under Germany's Excellence Strategy – EXC?2123 QuantumFrontiers – 390837967. The authors gratefully acknowledge M. Wenderoth and A. Sinterhauf for valuable discussions. This work was supported in part by the Joint Research Project ?GIQS? (18SIB07). This project received funding from the European Metrology Programme for Innovation and Research (EMPIR) co-financed by the Participating States and from the European Unions? Horizon 2020 research and innovation programme. A.A.Z. acknowledges the support from Stiftelsen f?r Strategisk Forskning (project RMA15-0024).?The authors thank DFG Project Te386/12-1 for their support. The authors also acknowledge the funding from the European Commission Graphene Flagship Core2 (grant agreement 785219). The work was co-funded by the?Deutsche Forschungsgemeinschaft?under Germany's Excellence Strategy ? EXC-2123 QuantumFrontiers ? 390837967. Open access funding enabled and organized by Projekt DEAL ",
year = "2020",
month = nov,
day = "4",
doi = "10.1002/adfm.202004695",
language = "English",
volume = "30",
journal = "Advanced functional materials",
issn = "1616-301X",
publisher = "Wiley-VCH Verlag",
number = "45",
}