Graphene is known to be single atomic 2 dimensional layer with hexagonal symmetry, and zero gap semiconductor. Graphene has a similar structure of graphite, which can be figured as one graphene sheet is moved horizontally and stacked vertically with AB layered structure with Van de Walls forces. Since Graphene is expected and shown to have unique electronic structure-related properties experimentally1 and theoretically2,3, it recently attracts many investigator to overcome Si device.
There are several methods to form gaphene sheet. Taping mechanically from HOPG is one of them and polymerizing method and crystallizing thermally from SiC are another. In this study, we investigated the basic electronic properties of grapheme which is obtained from SiC, using synchrotron Photoemission and NEXAFS, and the interaction between the molecules and graphene surface. Initial date tells that the graphene surface is electronically so stable, the molecules such as H2O, NH3, etc, cannot be chemisorbed on graphene surface at room temperature. Electron beam will be used to modify the graphene surface electronically. Later, the interaction between the modified graphene surface and a variety of molecules are investigated using PES, NEXAFS, and STM.
K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, I. V. Grigorieva, and A. A. Firsov, Science 306, 666 , 2004_.
2 K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, M. I. Katsnelson, I. V. Grigorieva, S. V. Dubonos, and A. A. Firsov, Nature, 438, 197 (2005).
3 Y. B. Zhang, Y.-W. Tan, H. L. Stormer, and Ph. Kim, Nature, 438, 201 (2005).
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