FORMATION OF $\sqrt {21} \times \sqrt {21} $ STRUCTURE BY GOLD DEPOSITION ON ${\rm{Si}}\left( {111} \right)\sqrt 3 \times \sqrt 3\mbox{-}{\rm{Ag}}$ SURFACE AND THE WAVERING BEHAVIOR

Abstract

Initial stage of gold deposition on a [Formula: see text] surface at room temperature is observed by reflection high-energy electron diffraction (RHEED) and scanning tunneling microscopy (STM). At gold coverage of 0.14 monolayer (ML) (here 1 ML=7.8×10 14 atoms/cm 2 ) a [Formula: see text] structure is formed on the surface. A model of the superstructure is proposed in terms of an embedded arrangement of three gold atoms in the unit cell. Wavering behavior of [Formula: see text] islands formed on the [Formula: see text] structure is found during STM observations.