The Doping Level of Graphene on Metal-coated SiOx Substrate: Its Raman Spectroscopy and Synchrotron Radiation Photoelectron Spectroscopy Study

• Main Authors: YunTsao, 曹雲
• Other Authors: Chung-Lin Wu
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/38052734910400663721

碩士 === 國立成功大學 === 物理學系碩博士班 === 100 === To develop novel graphene-based device, the carrier concentration of graphene has been studied widely recently. Through those researches, the doping level of graphene can be modulated by atom replacement, which may cause the 2-D structure damage or Electric Field Effect (EFE), which need to apply lots of extra electric filed. So far researches cannot find a simple way to tune the doping level of graphene. Owing to the differ¬ent work functions could induce charge transfer, we demonstrate Aluminum as well as Platinum-coated systems to support exfoliated graphene, and show that its doping level is captured in its Raman spectrum G peak stiffen. The G peak stiff¬en is explained as the vanishment of Kohn Anomalies (KAs) in reciprocal lattice points K and K'. Further, by Synchrotron Radiation Photoelectron Spectroscopy (SR-PES), we detect the C1s binding energy of different layers graphene on these two systems; afterwards, we get the experimental Electron Phonon Coupling (EPC) ~5.25 by combining the information from SR-PES and Raman spectrum. The agreement with the Density Functional Theory (DFT) value ~6.78 is excellent.