Large-Area Synthesis of High-Quality and Uniform Graphene Films on Copper Foils
Xuesong Li,1
Weiwei Cai,1
Jinho An,1
Seyoung Kim,2
Junghyo Nah,2
Dongxing Yang,1
Richard Piner,1
Aruna Velamakanni,1
Inhwa Jung,1
Emanuel Tutuc,2
Sanjay K. Banerjee,2
Luigi Colombo,3,*
Rodney S. Ruoff1,*
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.
2 Department of Electrical and Computer Engineering, Microelectronics Research Center, The University of Texas at Austin, Austin, TX 78758, USA.
3 Texas Instruments, Dallas, TX 75243, USA.
* To whom correspondence should be addressed. E-mail: colombo{at}ti.com (L.C.); r.ruoff{at}mail.utexas.edu (R.S.R.)
