Epitaxial graphene on SiC(0001) and \mathrm {SiC}(000\bar {1}) : from surface reconstructions to carbon electronics

摘要: Graphene with its unconventional two-dimensional electron gas properties promises a pathway towards nanoscaled carbon electronics. Large scale graphene layers for possible application can be grown epitaxially on SiC by Si sublimation. Here we report the initial growth of basal plane surfaces and relation to surface reconstructions. The were investigated scanning tunneling microscopy (STM), low energy diffraction (LEED), angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) x-ray (XPS). On SiC(0001) interface is characterized so-called [Formula: see text] reconstruction. homogeneity this phase influenced preparation procedure. Yet, it appears crucial quality further growth. We discuss role three structures periodicities text], (6 × 6) (5 5) present in phase. graphitization process observed distinct features STM images atomic resolution. number controlled conical band structure π-bands around point Brillouin zone as measured laboratory-based ARUPS using UV light from He II excitation. In addition show that spot intensity spectra LEED also used fingerprints exact determination first layers. data correlated results allow an easy practical method thickness analysis epitaxial applied continuously during procedure, thus paving way large variety experiments tune electronic future applications grows without presence layer. layer develops coexistence intrinsic reconstructions surface. high resolution measurements atomically resolved top (3 3) reconstruction Moire type modulation superlattice periodicity indicates weak coupling between substrate.