Studies of the Ag-Ge(100) interface

The growth mechanism, chemical interaction, crystallographic relationships, and electronic properties of Ag deposited at room temperature on Ge(100)-(2×1) were studied. Nucleation of deposited Ag at about monolayer coverage to form flat and metallic Ag(110) islands was observed with high-energy electron diffraction and photoemission from the valence bands. The growth of Ag at higher coverages was determined to be three dimensional. The 3d core levels of surface atoms of Ge(100)-(2×1) did not shift relative to the bulk with Ag coverage of a few monolayers, indicating a very weak interaction between Ag and Ge and negligible intermixing. Annealing experiments showed that the deposited Ag became highly clustered at elevated temperatures and did not wet the Ge(100)-(2×1) surface. We will compare the present results with those for Ag deposited on Ge(111).