ANGLE-RESOLVED PHOTOEMISSION-STUDIES OF CLEAN AND ADSORBED SI(001) SURFACES - 2X1, C(4X2), 2X1-NA AND 2X2-GA

Angle-resolved ultraviolet photoelectron spectroscopy (ARUPS) spectra of the wide-terrace single domain surfaces of Si(001)2 x 1, c(4 x 2), 2 x 1-Na, 2 x 1-Cs, 2 x 2-Ga and 2 x 3-Ga have been reported. For the Si(001)2 x 1 and c(4 x 2) surfaces, the resulting surface-state dispersions are consistent with those expected from the "antiferromagnetic" order of buckled dimer. For Si(001)2 x 1-alkali surfaces, surface-state dispersions of the three surfaces of 2 x 1-Na, 2 x 1-K and 2 x 1-Cs are summarized which are in principle consistent with the double-layer model of alkali adsorption. For Si(001)2 x 2-Ga and 2 x 3-Ga surfaces, the ARUPS results can be understood in terms of the Ga dimer model.