Au-induced reconstructions of the Si(111) surface

Au-adsorbed structures (~ 1 ML) on the Si(111) surface are studied using a scanning tunneling microscope. In the initial stage of deposition, locally Au atoms are adsorbed onto the Si (111) surface with a 5x5 periodicity. At lower coverage, images showing a 5x2 periodicity are recorded, in which there are a dark line and two atomic rows running in the [formula omitted] direction in a five times period. In each atomic row, atoms are arranged in a two times period along the row. At higher coverage, images showing a√3×√3 structure are also recorded. In these images, in addition to the√3×√3 periodicity, there is an undulation which is explained as a phase shift of the √3×√3 structure.