Electronic and Vibrational Properties · Figs. 42 - 71

This chapter illustrates electronic structure of surfaces for semiconductor Si(111)7 x 7, Ge(001), Ge(111)2 x 1, Ge(111)2 x 8. The reconstructed surface has a unit cell 49 times larger than that of the ideal Si(111) surface, but the number of atoms that are significantly displaced from their ideal bulk lattice site is considerably higher. A dimer-adatom-stacking fault (DAS) structure model has been found to be consistent with STM images and transmission electron-diffraction data. Experimental dispersion of the surface bands, inverse photoemission spectra, constant-distance tunneling conductance versus voltage spectra, distribution of broken bond states for Si(111)7 x 7 are figured out. Surface band structure and PBBS, partial-yield spectra, photoemission spectra, STM spectrum, EDCs of the Fermi level region of Ge(001) are also figured out. Projected valence band structure and occupied surface state dispersion, dispersion of occupied dangling bond states, band dispersion of the occupied dangling bond band, initial state energy dispersions, band dispersion for full and empty dangling bond bands of Ge(111)2 x 1 are illustrated. Experimental Ge(111) c(2 x 8) surface state dispersion, initial-state energy dispersion of surface structures observed by ARUPS from the Ge(111) annealed surface and energy dispersion of the surface structures observed by ARUPS spectra of Ge(111)2 x 8 are given.