非表示:
キーワード:
core level; dangling bonds; hydrogen termination; Mott-Hubbard transition; photoelectron spectroscopy; synchrotron radiation; valence band;STATE
要旨:
We report on highly resolved photoemission spectroscopy of hydrogenated 6H-SiC(0001) and 6H-SiC(000 (1) over bar) surfaces. Chemically shifted components in the core level spectra are identified and discussed. Photon induced desorption of hydrogen due to high doses of synchrotron radiation leads to hydrogen-free and unreconstructed (1x1)-surfaces with dangling bond states within the fundamental band gap below E-F. The Mott-Hubbard picture is discussed as a possible explanation for the semi-conducting nature of unreconstructed SiC surfaces.
