Applying time-dependent photoemission we unravel the graphene growth process
on a metallic surface by chemical vapor deposition (CVD). Graphene CVD growth
is in stark contrast to the standard growth process of two--dimensional films
because it is self-limiting and stops as soon as a monolayer graphene has been
synthesized. Most importantly, a novel phase of metastable graphene was
discovered that is characterized by permanent and simultaneous construction and
deconstruction. The high quality and large area graphene flakes are
characterized by angle-resolved photoemission proofing that they are indeed
monolayer and cover the whole 1×1 cm Nickel substrate. These findings
are of high relevance to the intensive search for reliable synthesis methods
for large graphene flakes of controlled layer number