Hydrogen-induced3×1phase of the Si-rich3C−SiC(001)surface

A single-domain $3\times 1$ phase induced by hydrogen adsorption on a Si-rich $3C-\mathrm{SiC}\mathrm{}\left(001\right)3\times 2$ surface is investigated by photoemission using synchrotron radiation. Three surface components of the Si $2p$ core level are identified for the $3\times 1-\mathrm{H}$ phase, which resemble those of the $3\times 2$ surface. A H-Si bonding state is observed by angle-resolved valence-band photoemission. These results are consistent with the recent assignments of the Si $2p$ surface components and the valence band spectra of the $3\times 2$ surface, based on the $3\times 2$ structure model with $\frac{2}{3}$ ML Si addimers. A straightforward $3\times 1-\mathrm{H}$ structure model is introduced featuring Si dimer-bond breaking and dangling-bond saturation.