Atomic structures of the two-dimensional Ag layer grown on Si(001)-(2 × 1) at room temperature have been studied by coaxial impact collision ion scattering spectroscopy. After several monolayers of Ag had been deposited on the Si(001)-(2 × 1) surface, the two-dimensional Ag layer was found to consist of Ag dimers. The bond length of the Ag dimer was 2.89 ± 0.05 Å. The heights of the Ag dimers from the second Si layer were 2.45 and 3.02 A. The Ag dimers were located in the hollow sites between two dimers along the Si row, and in the middle of four neighbouring Si dimers with the orientation of the Ag dimer row being perpendicular to that of the Si dimer. Thus, the Si substrate under the two-dimensional Ag layer still retained its initial dimer structure. Therefore, it was concluded that the two-dimensional Ag layer on Si(001)-(2 × 1) had a Ag(2 × 2) structure with a saturation coverage of 1 ML.
Bibliographical noteFunding Information:
This work was supported by BSRI program (BSRI-97-2426) and KOSEF through the Atomic-scale Surface Science Research Center at Yonsei University.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry