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The quasi-free-standing nature of graphene on H-saturated SiC(0001)

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 نشر من قبل Thomas Seyller
 تاريخ النشر 2011
  مجال البحث فيزياء
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We report on an investigation of quasi-free-standing graphene on 6H-SiC(0001) which was prepared by intercalation of hydrogen under the buffer layer. Using infrared absorption spectroscopy we prove that the SiC(0001) surface is saturated with hydrogen. Raman spectra demonstrate the conversion of the buffer layer into graphene which exhibits a slight tensile strain and short range defects. The layers are hole doped (p = 5.0-6.5 x 10^12 cm^(-2)) with a carrier mobility of 3,100 cm^2/Vs at room temperature. Compared to graphene on the buffer layer a strongly reduced temperature dependence of the mobility is observed for graphene on H-terminated SiC(0001)which justifies the term quasi-free-standing.



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This paper has been withdrawn due to the adherance to the double submission policies of a refereed journal. Our apologies.
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