Graphene: Patterned Growth of Graphene over Epitaxial Catalyst Small 11/2010

The cover picture illustrates the formation of a triangular graphene film inside a pit of epitaxial metal catalyst. Rectangular- and triangular-shaped microscale graphene films are grown on epitaxial Co films deposited on single-crystal MgO substrates with (001) and (111) planes, respectively. Thermal decomposition of polystyrene over the epitaxial metal film in high vacuum gives unique pits, whose orientation and shape are strongly dependent on the crystallographic orientation of the MgO substrate. Raman-mapping measurements reveal preferential formation of few-layer-graphene films inside these pits. These graphene films are transferred onto a SiO2/Si substrate while maintaining the original shape, and field-effect transistors are fabricated using the transferred films. These findings offer lithography-free patterned growth of graphene for future electronics. For more information, please read the Full Paper “Patterned Growth of Graphene over Epitaxial Catalyst” by H. Ago et al., beginning on page 1226.