Atomic and electronic structures of Ag/Si(100)-c(6×2) surface: A first-principles study

Ag-induced Si(100) reconstruction: Si(100)-(22×22)R45∘

“…As shown in Fig. 1(c), the elongated ring-shaped features on the surface also form a periodic structure in which the basic unit is a square with the side of 1.09 nm and the vectors a 2 [11][12][13][14][15][16] it is immediately concluded that this reconstruction with elongated rings as building blocks is an uncovered Ag-induced Si(100) reconstruction.…”

“…[11][12][13][14][15][16] The relaxed structure [ Fig. 2(c)] clearly reveals that the Ag atoms on the dimer row have a different adsorption behavior: the Ag atom breaks down the attached Si dimer and forms bonds to these two Si atoms with a bond length of 0.245 nm.…”

“…Therefore, we consider that the Ag atoms on the Si(100)-(2 × 2)-Ag reconstruction are actually located on the top of the Si dimers rather than on the bridge sites between the dimers as suggested in Ref. 11.…”

“…[1][2][3][4][5][6][7][8][9][10] For Ag/Si(100), a prototype metal/semiconductor system, a variety of reconstructions, e.g., Si(100)-(2 × 1)-Ag, Si(100)-(2 × 2)-Ag, Si(100)-(2 × 3)-Ag and Si(100)-(6 × 2)-Ag, [11][12][13][14][15][16] have been fabricated by depositing Ag atoms onto Si(100) surfaces plus postannealing processes at various temperatures. These reconstructions have been widely investigated by low-energy electron diffraction, photoemission, and scanning tunneling microscopy (STM).…”

“…Although the structural models for these reconstructions are still in question, it is proposed that the Ag atoms are adsorbed at the bridge sites between Si dimers or in the grooves between neighboring Si dimer rows. [11][12][13][14][15][16] This Brief Report describes observations of the presence of a different adsorption site for Ag atoms on the Si(100) surface and the corresponding uncovered reconstruction: Si(100)-(2 √ 2 × 2 √ 2)R45 • -Ag. High-resolution scanning tunneling microscopy images reveal that Si dimers were broken by adsorption of Ag atoms and the basic unit of the reconstruction contains two Ag atoms bonded to Si dimers and two Ag atoms located at the grooves between the neighboring dimer rows.…”