Kinetics of Au induced faceting of vicinal Si(111)

An induced faceting of vicinal Si(I 1 1) has been studied during adsorption at elevated temperature by spot profile analyzing of low energy electron diffraction and after quenching to room temperature by scanning tunneling microscopy. On the surfaces inclined towards [112] five different types of facets form with increasing Au coverage at adsorption temperatures T-ads, below 800 degreesC. They are (4 4 3), (7 7 5), (5 5 3), a stepped (2 2 1), and the (3 3 1) facets. Atomic models for the (5 5 3) and (7 7 5) facet planes are proposed on the basis of high resolution STM images. At T-ads = 800 degreesC we found the formation of an ordered step train which covers the entire surface. With further increasing Au coverage the stepped surface decomposes again into (I 1 1) terraces and step bunches. Driving force is the formation of the Si(I 1 1)-(5 x 2)-Au reconstruction. (C) 2002 Elsevier Science B.V. All rights reserved.