  We have performed scanning tunneling microscope (STM) and angle-resolved
photoemission spectroscopy (ARPES) in Pb-deposited bilayer Graphene (BLG) on
SiC(0001) substrate to investigate the dependence of the electronic structures
on Pb-deposition amount. We have observed that the Pb atoms form islands by STM
and the ${\pi}$ bands of the BLG shift toward the Fermi level by ARPES. This
hole-doping-like energy shift is enhanced as the amount of Pb is increased, and
we were able to tune the Dirac gap to the Fermi level by 4 ML deposition.
Considering the band dispersion, we suggest that hole-doping-like effect is
related to the difference between the work functions of Pb islands and BLG/SiC;
the work function of BLG/SiC is lower than that of Pb. Our results propose an
easy way of band tuning for graphene with appropriate selection of both the
substrate and deposited material.
