Si clusters on reconstructed SiC (0001) revealed by surface extended x-ray absorption fine structure

Xingyu Gao; Shi Chen; Tao Liu; Wei Chen; Wee, A. T. S.; Nomoto, T.; Yagi, S.; Soda, Kazuo; Yuhara, Junji
October 2009
Applied Physics Letters;10/5/2009, Vol. 95 Issue 14, p144102
Academic Journal
The evolution of silicon carbide (0001) surface reconstruction upon annealing has been studied by Si K edge extended x-ray absorption fine structure (EXAFS). Using Si KVV Auger electron yield at different emission angles with different surface sensitivities, EXAFS reveals conclusively that Si–Si bonds exist on the surface for all reconstructions. The existence of Si clusters on the 63×63R30° surface was also confirmed by x-ray photoemission spectroscopy. This finding gives us a better understanding of epitaxial graphene formation on SiC.


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