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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Surface potentials and layer charge distributions in few-layer graphene films.
Sujit S Datta1, Douglas R Strachan, E J Mele
1Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Nano Letters
|July 11, 2008
Summary
Few-layer graphene (FLG) films show unique surface potential behavior on insulating substrates, unlike conventional materials. This finding is crucial for advancing graphene-based nanoelectronics and postsilicon devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphene-derived nanomaterials are promising for postsilicon electronics.
- Understanding substrate-graphene electronic interactions is key for device development.
Purpose of the Study:
- To investigate the electronic interaction between insulating substrates and few-layer graphene (FLG) films.
- To elucidate the relationship between FLG thickness and surface potential.
Main Methods:
- Electrostatic Force Microscopy (EFM) was employed to measure surface potential.
- Analysis of electronic perturbations along crystallographic directions in disordered FLGs.
Main Results:
- FLG surface potential increases with film thickness, reaching a bulk value at five or more layers.
- Observed behavior contrasts with conventional conductors/semiconductors, attributed to graphene's unique charge screening.
- EFM revealed electronic perturbations linked to atomic defects in disordered FLGs.
Conclusions:
- Graphene's relativistic carriers dictate unique charge screening mechanisms.
- These findings have significant implications for graphene nanoelectronics design.
- EFM provides a powerful tool for characterizing graphene electronic properties.
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