First-Principles Study of Graphene-6H SiC Surface Interactions

First-principles study of preferential sites of hydrogen incorporated in epitaxial graphene on 6H-SiC(0001)

The hydrogen H incorporation in the epitaxial graphene buffer layer on 6H-SiC 0001 with various H coverages is investigated using the density-functional method. The most stable site for a single H atom is on top of a threefold C atom in the graphene buffer layer, whereas the incorporation into the interfacial layer is less favored. However, when the H concentration is above 7.15 1014 cm−2, the ...

Hydrogen intercalation of graphene grown on 6H-SiC(0001)

Atomic hydrogen exposures on a monolayer graphene grown on the SiC(0001) surface are shown to result in hydrogen intercalation. The hydrogen intercalation induces a transformation of the monolayer graphene and the carbon buffer layer to bi-layer graphene without a buffer layer. The STM, LEED, and core-level photoelectron spectroscopy measurements reveal that hydrogen atoms can go underneath the...

Multiscale investigation of graphene layers on 6H-SiC(000-1)

In this article, a multiscale investigation of few graphene layers grown on 6H-SiC(000-1) under ultrahigh vacuum (UHV) conditions is presented. At 100-μm scale, the authors show that the UHV growth yields few layer graphene (FLG) with an average thickness given by Auger spectroscopy between 1 and 2 graphene planes. At the same scale, electron diffraction reveals a significant rotational disorde...

Si intercalation/deintercalation of graphene on 6H-SiC(0001)

The intercalation and deintercalation mechanisms of Si deposited on monolayer graphene grown on SiC(0001) substrates and after subsequent annealing steps are investigated using low-energy electron microscopy (LEEM), photoelectron spectroscopy (PES), and micro-low-energy electron diffraction (μ-LEED). After Si deposition on samples kept at room temperature, small Si droplets are observed on the ...

Graphoepitaxy of High-Quality GaN Layers on Graphene/6H-SiC