skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Tuning carrier density across Dirac point in epitaxial graphene on SiC by corona discharge

Abstract

We demonstrate reversible carrier density control across the Dirac point (Δn ∼ 10{sup 13 }cm{sup −2}) in epitaxial graphene on SiC (SiC/G) via high electrostatic potential gating with ions produced by corona discharge. The method is attractive for applications where graphene with a fixed carrier density is needed, such as quantum metrology, and more generally as a simple method of gating 2DEGs formed at semiconductor interfaces and in topological insulators.

Authors:
; ; ;  [1];  [2];  [3];  [4];  [3];  [5]
  1. Department of Microtechnology and Nanoscience, Chalmers University of Technology, S-41296 Göteborg (Sweden)
  2. SP Technical Research Institute of Sweden, S-50115 Borås (Sweden)
  3. National Physical Laboratory, Teddington TW110LW (United Kingdom)
  4. (United Kingdom)
  5. Department of Physics, Chemistry and Biology (IFM), Linköping University, S-58183 Linköping (Sweden)
Publication Date:
OSTI Identifier:
22318097
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARRIER DENSITY; CORONA DISCHARGES; EPITAXY; GRAPHENE; SEMICONDUCTOR MATERIALS; SILICON CARBIDES

Citation Formats

Lartsev, Arseniy, Yager, Tom, Lara-Avila, Samuel, E-mail: samuel.lara@chalmers.se, Kubatkin, Sergey, Bergsten, Tobias, Tzalenchuk, Alexander, Royal Holloway, University of London, Egham TW20 0EX, Janssen, T. J. B. M, and Yakimova, Rositza. Tuning carrier density across Dirac point in epitaxial graphene on SiC by corona discharge. United States: N. p., 2014. Web. doi:10.1063/1.4892922.
Lartsev, Arseniy, Yager, Tom, Lara-Avila, Samuel, E-mail: samuel.lara@chalmers.se, Kubatkin, Sergey, Bergsten, Tobias, Tzalenchuk, Alexander, Royal Holloway, University of London, Egham TW20 0EX, Janssen, T. J. B. M, & Yakimova, Rositza. Tuning carrier density across Dirac point in epitaxial graphene on SiC by corona discharge. United States. doi:10.1063/1.4892922.
Lartsev, Arseniy, Yager, Tom, Lara-Avila, Samuel, E-mail: samuel.lara@chalmers.se, Kubatkin, Sergey, Bergsten, Tobias, Tzalenchuk, Alexander, Royal Holloway, University of London, Egham TW20 0EX, Janssen, T. J. B. M, and Yakimova, Rositza. Mon . "Tuning carrier density across Dirac point in epitaxial graphene on SiC by corona discharge". United States. doi:10.1063/1.4892922.
@article{osti_22318097,
title = {Tuning carrier density across Dirac point in epitaxial graphene on SiC by corona discharge},
author = {Lartsev, Arseniy and Yager, Tom and Lara-Avila, Samuel, E-mail: samuel.lara@chalmers.se and Kubatkin, Sergey and Bergsten, Tobias and Tzalenchuk, Alexander and Royal Holloway, University of London, Egham TW20 0EX and Janssen, T. J. B. M and Yakimova, Rositza},
abstractNote = {We demonstrate reversible carrier density control across the Dirac point (Δn ∼ 10{sup 13 }cm{sup −2}) in epitaxial graphene on SiC (SiC/G) via high electrostatic potential gating with ions produced by corona discharge. The method is attractive for applications where graphene with a fixed carrier density is needed, such as quantum metrology, and more generally as a simple method of gating 2DEGs formed at semiconductor interfaces and in topological insulators.},
doi = {10.1063/1.4892922},
journal = {Applied Physics Letters},
number = 6,
volume = 105,
place = {United States},
year = {Mon Aug 11 00:00:00 EDT 2014},
month = {Mon Aug 11 00:00:00 EDT 2014}
}
  • We report the electron transport properties of epitaxial graphene (EG) grown on 4H-SiC (0001) by low energy electron-beam irradiation. As-grown EG (AEG) on SiC interface exhibits rectifying current-voltage characteristics with a low Schottky barrier (SB) of 0.55 ± 0.05 eV and high reverse current leakage. The SB of AEG/SiC junction is extremely impeded by the Fermi level pinning (FLP) above the Dirac point due to charged states at the interface. Nevertheless, a gentle hydrogen intercalation at 900 °C enables the alleviation of both FLP and carrier scattering owing to the saturation of dangling bonds as evidenced by the enhancement of SB (0.75 ± 0.05 eV) and highmore » electron mobility well excess of 6000 cm{sup 2} V{sup −1} s{sup −1}.« less
  • To investigate the high magnetic field properties of the Dirac fermion system, we performed magneto-absorption measurements of epitaxially grown graphene at high magnetic field using the single-turn coil (STC) method. We observed the cyclotron resonance absorption corresponding to n = 0 to 1 intraband transitions.
  • Hot carrier dynamics in the Dirac band of n-type epitaxial graphene on a SiC substrate were traced in real time using femtosecond-time-resolved photoemission spectroscopy. The spectral evolution directly reflects the energetically linear density of states superimposed with a Fermi–Dirac distribution. The relaxation time is governed by the internal energy dissipation of electron–electron scattering, and the observed electronic temperature indicates cascade carrier multiplication.
  • Raman spectroscopy and scanning tunneling microscopy/spectroscopy measurements are performed to determine the atomic structure and electronic properties of H-intercalated graphene/SiC(0001) obtained by annealing the as-grown epitaxial graphene in hydrogen atmosphere. While the as-grown graphene is found to be n-type with the Dirac point (E{sub D}) at 450 and 350 meV below Fermi level for the 1st and 2nd layer, the H-intercalated graphene is p-type with E{sub D} at 320 and 200 meV above. In addition, ripples are observed in the now quasi-free standing graphene decoupled from the SiC substrate. This causes fluctuations in the Dirac point that directly follow the undulations ofmore » the ripples, resulting in electron and hole puddles in the H-intercalated graphene/SiC(0001)« less
  • In this letter, we report the UV detection characteristics of an epitaxial graphene (EG)/SiC based Schottky emitter bipolar phototransistor (SEPT) with EG on top as the transparent Schottky emitter layer. Under 0.43 μW UV illumination, the device showed a maximum common emitter current gain of 113, when operated in the Schottky emitter mode. We argue that avalanche gain and photoconductive gain can be excluded, indicating minority carrier injection efficiency, γ, as high as 99% at the EG/p-SiC Schottky junction. This high γ is attributed to the large, highly asymmetric barrier, which EG forms with the p-SiC. The maximum responsivity of themore » UV phototransistor is estimated to be 7.1 A/W. The observed decrease in gain with increase in UV power is attributed to recombination in the base region, which reduces the minority carrier lifetime.« less