Graphene has been advertised both as a unique electron system for 2D physics research and as a
platform for carbon electronics. Despite these claims, only a few of the fundamental properties of an
isolated graphene sheet have been demonstrated in a single system. This is because of substrate
interactions in both exfoliated graphene on SiO2 and epitaxial graphene grown on the Si-face of SiC.
Disorder even in supported exfoliated films and the inability to scale these geometries to large circuit
platforms reflect similar problems that have plagued carbon nanotubes for more than two decades and
prevented them from any significant role in post Si-CMOS technologies. Despite these sobering
realities, an all carbon electronics system is still very likely. The remarkable finding is that the system
most likely to be developed into a carbon electronics paradigm is the one initially dismissed by
graphene researchers. I will show that only one graphene system has demonstrated the properties
expected for an isolated graphene sheet: multilayer epitaxial graphene (MEG) grown on the C-face of
SiC. MEG not only shows all the 2D properties expected for an isolated graphene sheet, but has the
scalability to be expanded to large scale integrated carbon circuits. I will show that the reason for this
remarkable property, i.e. a multilayer graphene films behaving like a single graphene sheet, is due to
MEG’s unique stacking. MEG films have a quasi-ordered rotational stacking that breaks the Bernal
stacking symmetry associated with both graphite and thin graphene sheets grown on the Si-face of SiC.
LEED, X-ray scattering, ARPES and transport measurements will all be presented that demonstrate the
MEG’s isolated graphene electronic properties. I will also show how furnace grown MEG films on the
C-face can be produced in exceptional sizes. Growth on step free regions up to 40microns with film
thickness variations of one layer over millimeters can now be achieved and seem to be only limited by
the SiC substrate perfection.
https://mediaspace.gatech.edu/media/conrad/1_5qrham2r
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