Efficient transfer of graphene for improvement of G based devices

Efficient transfer of graphene for improvement of G based devices

Graphene although dubbed wonder material, capable of a vast range of applications and properties, can not be grown directly on the desired location. Graphene synthesis has come a long way since the scotch tape method used on time of its discovery. 

A group of European Scientists from Italy, Switzerland and Sweden have compared the"Graphene Growth on Cu(111) versus Oxidized Cu(111)". http://pubs.acs.org/doi/abs/10.1021/nl5036463

 Abstract: The epitaxial growth of graphene on catalytically active metallic surfaces via chemical vapor deposition (CVD) is known to be one of the most reliable routes toward high-quality large-area graphene. This CVD-grown graphene is generally coupled to its metallic support resulting in a modification of its intrinsic properties. Growth on oxides is a promising alternative that might lead to a decoupled graphene layer. Here, we compare graphene on a pure metallic to graphene on an oxidized copper surface in both cases grown by a single step CVD process under similar conditions. Remarkably, the growth on copper oxide, a high-k dielectric material, preserves the intrinsic properties of graphene; it is not doped and a linear dispersion is observed close to the Fermi energy. Density functional theory calculations give additional insight into the reaction processes and help explaining the catalytic activity of the copper oxide surface.

The authors question the commonly held belief that the catalytic activity of the copper oxide for  graphene growth is low needs to be reconsidered and that CVD growth on metal oxides surfaces is a promising route for the fabrication of graphene, as well as of graphene nanostructures, on high k dielectric substrates via industrially scalable and versatile methods.

their experiments have shown that high quality free standing graphene can be grown directly on an oxidized copper surface. The possibility of graphene growth on a high k dielectric copper oxide surface, while preserving a freestanding like graphene band structure, has great implications for the development of graphene based electronics

Structural characterization of graphene grown on Cu(111) and on oxidized Cu(111).

 

 

 

 

(a) STM image (170 nm x 170 nm) for graphene grown on Cu(111). A Moiré pattern arising due to the lattice mismatch between graphene and Cu(111) is visible which continues over the step edges. (b) STM image (6.8 nm x 6.8 nm) showing atomic resolution with the Moiré patternpresent in the background. (c) LEED pattern of graphene grown on Cu(111) taken at a primary energy of 150 eV. In addition to the Cu(111) diffraction spots (lattice vectors in light blue), a ring surrounding these spots is visible which is related to the presence of graphene. (d) STM image (17 nm x 17 nm) of graphene grown on oxidized Cu(111). A diffuse background coming from the oxide is visible. (e) STM image for graphene grown on oxidized Cu(111) (4.3 nm x 4.3 nm) showing atomic resolution. (f) LEED pattern of graphene grown on oxidized Cu(111) taken at a primary energy of 61 eV. The high intensity di ffraction spots arise from the oxidized Cu(111) (lattice vectors in red) while the spots marked in orange indicate the presence ofgraphene (see also Fig. 2a, b)