-A A +A
Local current transport across graphene/4H-SiC was studied with nanometric scale lateral resolution by Scanning Current Spectroscopy on both graphene grown epitaxially on 4H-SiC (0001)(EG-SiC) and graphene exfoliated from highly oriented pyrolitic graphite and deposited on 4H-SiC (0001)(DG-SiC). The study revealed that the Schottky barrier height (SBH) of EG/4H-SiC (0001) is lowered by~ 0.49 eV. This is explained in terms of Fermi-level pinning above the Dirac point in EG due to the presence of positively charged states at the interface between Si face of 4H-SiC and carbon-rich buffer layer. Furthermore, Scanning Capacitance Spectroscopy based method allowed evaluating local electron mean free path (lgr) in graphene. lgr in EG-SiC was observed to be, on average,~ 0.4 times that in DG-SiC and exhibited large point-to-point variations due to presence of laterally homogeneous positively charged …
Trans Tech Publications Ltd
Publication date: 
1 Jan 2011

Sushant Sonde, Carmelo Vecchio, Filippo Giannazzo, Rositza Yakimova, Emanuele Rimini, Vito Raineri

Biblio References: 
Volume: 679 Pages: 769-776
Materials Science Forum