Current annealing and electrical breakdown of epitaxial graphene

Epitaxial Graphene and Graphene–Based Devices Studied by Electrical Scanning Probe Microscopy

We present local electrical characterization of epitaxial graphene grown on both Siand C-faces of 4H-SiC using Electrostatic Force Microscopy and Kelvin Probe Force Microscopy in ambient conditions and at elevated temperatures. These techniques provide a straightforward identification of graphene domains with various thicknesses on the substrate where topographical determination is hindered by ...

Epitaxial graphene

Graphene multilayers are grown epitaxially on single crystal silicon carbide. This system is composed of several graphene layers of which the first layer is electron doped due to the built-in electric field and the other layers are essentially undoped. Unlike graphite the charge carriers show Dirac particle properties (i.e. an anomalous Berry’s phase, weak anti-localization and square root fiel...

Transforming amorphous carbon into graphene by current- induced annealing

ABSTRACT: We report on the catalyst-free growth of graphene from amorphous carbon (a-C) by current-induced annealing. This is a novel mechanism that we could witness by in-situ transmission electron microscopy and simulate with molecular dynamics calculations. We observe that small a-C clusters on a graphene substrate rearrange and crystallize into graphene patches due to the high temperatures ...

Phase Space for the Breakdown of the Quantum Hall Effect in Epitaxial Graphene

Free-standing epitaxial graphene.

We report on a method to produce free-standing graphene sheets from epitaxial graphene on silicon carbide (SiC) substrate. Doubly clamped nanomechanical resonators with lengths up to 20 microm were patterned using this technique and their resonant motion was actuated and detected optically. Resonance frequencies of the order of tens of megahertz were measured for most devices, indicating that t...