Angle-resolved photoemission studies of the 3C-SiC(001)(2 x 1) surface

We have investigated the electronic structure of the single-domain 3C-SiC(0 01)(2 x 1) using angle-resolved photoemission and synchrotron radiation. Tw o different surface-state bands are clearly identified within the bulk band gap. The upper band has a binding energy of 1.4 eV at the center of the sur face Brillouin zone (SBZ) and shows a weak dispersion of 0.3 eV in the <(Ga mma)over bar> - (J) over bar direction, but is nondispersive in the perpend icular direction. It has a polarization dependence suggesting a p(x) charac ter, as expected for a Si dangling-bond state. The second band is located a t 2.4 eV binding energy and is nondispersive. The weak or nonexistent dispe rsions suggest very localized electronic states at the surface and show poo r agreement with calculated dispersions for the proposed models for the 2 x 1 and c(4 x 2) reconstructions.