Adsorption Of H On Si(111)-Square-Root-3 X Square-Root-3-Ag - Evidence For Ag(111) Agglomerates Formation

In this low-energy ion scattering study we find that the reaction of H with Si(111)-square-root 3 x square-root 3-Ag results in an extensive surface modification. Saturated adsorption of H of about 1.5 ML coverage below 100-degrees-C transforms an uniform Ag monolayer in the square-root 3 x square-root 3 lattice into very small crystallites of Ag(111) grown epitaxially on the Si(111) substrate. The thickness of the Ag(111) crystallites is found to be three atomic layers. When only H is thermally desorbed by moderate heating above 400-degrees-C, the crystallite disappears and the original square-root 3 x square-root 3-Ag is recovered.