ELECTRONIC-STRUCTURES OF THE SI(001)2X3-IN SURFACE

Electronic structures of a single-domain Si(001)2x3-In surface were in vestigated by polarization-dependent angle-resolved-photoelectron spec troscopy (ARPES) using synchrotron radiation: Six surface-state bands, denoted as D, S-1, S-2, S-2', S-3, and S-3', are identified within th e bulk band gap, whose dispersions and symmetry properties are determi ned throughout the surface Brillouin zone. From these results and a co mparison with the recent ARPES results on Si(001)2x2-In [H. W. Yeom et al., Phys. Rev. B 53, 1948 (1996)], the origins of the surface states are assigned as the dangling-bond state (D) of Si dimers not bonded t o In dimers, the dimer-bond state (S-1) of In dimers, and the backbond states (S-2, S-2', S-3, and S-3') due to the bonds between In and Si dimers.