Growth of large-area single- and Bi-layer graphene by controlled carbon precipitation on polycrystalline Ni surfaces
Graphene, chemical vapor deposition, nickel catalyst, carbon nanomaterials
We report graphene films composed mostly of one or two layers of graphene grown by controlled carbon precipitation on the surface of polycrystalline Ni thin films during atmospheric chemical vapor deposition (CVD). Controlling both the methane concentration during CVD and the substrate cooling rate during graphene growth can signiﬁ cantly improve the thickness uniformity. As a result, one- or two- layer graphene regions occupy up to 87% of the ﬁ lm area. Single layer coverage accounts for 5% 11% of the overall ﬁ lm. These regions expand across multiple grain boundaries of the underlying polycrystalline Ni ﬁ lm. The number density of sites with multilayer graphene/graphite (>2 layers) is reduced as the cooling rate decreases. These ﬁ lms can also be transferred to other substrates and their sizes are only limited by the sizes of the Ni ﬁ lm and the CVD chamber. Here, we demonstrate the formation of ﬁ lms as large as 1 in2 . These ﬁ ndings represent an important step towards the fabrication of large-scale high-quality graphene samples.
Tsinghua University Press
Alfonso Reina,Stefan Thiele,Xiaoting Jia,Sreekar Bhaviripudi,Mildred S. Dresselhaus,Juergen A. Schaefer,Jing Kong, Growth of large-area single- and Bi-layer graphene by controlled carbon precipitation on polycrystalline Ni surfaces. NanoRes.2009, 2: 509-516