am6b03705_si_001.pdf (490.29 kB)
AC-Impedance Spectroscopic Analysis on the Charge Transport in CVD-Grown Graphene Devices with Chemically Modified Substrates
journal contribution
posted on 2016-08-30, 00:00 authored by Bok Ki Min, Seong K. Kim, Seong Ho Kim, Min-A Kang, Suttinart Noothongkaew, Edmund M. Mills, Wooseok Song, Sung Myung, Jongsun Lim, Sangtae Kim, Ki-Seok AnA comprehensive study for the effect
of interfacial buffer layers on the electrical transport behavior
in CVD-grown graphene based devices has been performed by ac-impedance
spectroscopy (IS) analysis. We examine the effects of the trap charges
at graphene/SiO2 interface on the total capacitance by
introducing self-assembled monolayers (SAMs). Furthermore, the charge
transports in the polycrystalline graphene are characterized through
the temperature-dependent IS measurement, which can be explained by
the potential barrier model. The frequency-dependent conduction reveals
that the conductivity of graphene is related with the mobility, which
is limited by the scattering caused by charged adsorbates on SiO2 surface.