Large-area synthesis of high-quality and uniform graphene films on copper foils.
Graphene has been attracting great interest because of its distinctive band structure and physical properties. Today, graphene is limited to small sizes because it is produced mostly by exfoliating graphite. We grew large-area graphene films of the order of centimeters on copper substrates by chemical vapor deposition using methane. The films are predominantly single-layer graphene, with a small percentage (less than 5%) of the area having few layers, and are continuous across copper surface steps and grain boundaries. The low solubility of carbon in copper appears to help make this growth process self-limiting. We also developed graphene film transfer processes to arbitrary substrates, and dual-gated field-effect transistors fabricated on silicon/silicon dioxide substrates showed electron mobilities as high as 4050 square centimeters per volt per second at room temperature.
Department of Mechanical Engineering and the Texas Materials Institute, 1 University Station C2200, University of Texas at Austin, Austin, TX 78712-0292, USA.
Xuesong
X
Li
Weiwei
W
Cai
Jinho
J
An
Seyoung
S
Kim
Junghyo
J
Nah
Dongxing
D
Yang
Richard
R
Piner
Aruna
A
Velamakanni
Inhwa
I
Jung
Emanuel
E
Tutuc
Sanjay K
SK
Banerjee
Luigi
L
Colombo
Rodney S
RS
Ruoff