Enhancing
the Electrical Properties of a Flexible
Transparent Graphene-Based Field-Effect Transistor Using Electropolished
Copper Foil for Graphene Growth
- Publication date
- Publisher
Abstract
Flexible
transparent graphene-based field-effect transistors (Gr-FETs)
were fabricated using large-area single-layer graphene synthesized
through low-pressure chemical vapor deposition on a pretreated copper
(Cu) foil, followed by transfer of the graphene from the Cu foil to
a poly(ethylene terephthalate) (PET) substrate. The electropolishing
method was adopted to smooth the surface of the Cu foil, which is
a crucial factor because it affects the defect density of graphene
films on the PET substrate after transfer and the electronic transport
property of the graphene-based devices. The influence of the electropolishing
process on the graphene properties was examined using a Raman spectroscope,
a scanning electron microscope, and an optical microscope. When the
electropolishing process was adopted to improve the graphene quality,
the carrier mobility of the flexible transparent Gr-FETs was enhanced
from 90 to 340 cm<sup>2</sup>/(V s). Furthermore, variation of the
carrier mobility was lower than 10% when the bending radius of the
flexible device was decreased from 6.0 to 1.0 cm