  We have used scanning gate microscopy to explore the local conductivity of a
current-annealed graphene flake. A map of the local neutrality point (NP) after
annealing at low current density exhibits micron-sized inhomogeneities.
Broadening of the local e-h transition is also correlated with the
inhomogeneity of the NP. Annealing at higher current density reduces the NP
inhomogeneity, but we still observe some asymmetry in the e-h conduction. We
attribute this to a hole doped domain close to one of the metal contacts
combined with underlying striations in the local NP.
