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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Surface doping and band gap tunability in hydrogenated graphene
Bernard R Matis1, James S Burgess, Felipe A Bulat
1NRC Postdoctoral Associate, Naval Research Laboratory, Washington, DC 20375, USA.
ACS Nano
|December 23, 2011
Summary
Researchers observed n-type hydrogenated graphene and converted it to p-type using surface doping. This breakthrough in graphene electronics opens possibilities for novel p-n junctions.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Surface Science
Background:
- Graphene's unique electronic properties make it a promising material for next-generation electronics.
- Controlling the carrier type (electron or hole) in graphene is crucial for device applications.
- Hydrogenation of graphene is a method to modify its electronic structure.
Purpose of the Study:
- To investigate the carrier type of hydrogenated graphene on SiO(2).
- To demonstrate the conversion of majority carrier type in hydrogenated graphene.
- To explore the impact of hydrogenation on graphene's band gap and its tunability.
Main Methods:
- Experimental observation of n-type behavior in hydrogenated graphene on SiO(2).
- Surface doping techniques to convert carrier type from electrons to holes.
- Density functional theory (DFT) calculations to understand work function changes.
- Temperature-dependent electronic transport measurements to analyze band gap properties.
Main Results:
- First observation of n-type behavior in hydrogenated graphene on SiO(2).
- Successful conversion of majority carriers from electrons to holes via surface doping.
- Hydrogenation induces a tunable band gap in graphene, with maximum value at the charge neutrality point.
- Band gap is dependent on hydrogen coverage and electric field effect.
Conclusions:
- The carrier type reversal is linked to the work function of hydrogenated graphene relative to the substrate.
- Hydrogenated graphene exhibits a tunable band gap, controllable via electric field and hydrogen coverage.
- Chemically modified graphene with controlled carrier type and band gap opens potential for p-n junction devices.
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