AVS 47th International Symposium
    Surface Science Wednesday Sessions
       Session SS-WeP

Paper SS-WeP7
Growth of a Group-IV Metal on Si(5 5 12)

Wednesday, October 4, 2000, 11:00 am, Room Exhibit Hall C & D

Session: Poster Session
Presenter: I. Samanta, Virginia Commonwealth University
Authors: I. Samanta, Virginia Commonwealth University
A.A. Baski, Virginia Commonwealth University
Correspondent: Click to Email
Recently, we have used scanning tunneling microscopy (STM) to study the growth behavior of noble metals (Ag, Au) on the row-like Si(5 5 12) surface.@footnote 1@ In this study, we explore the different growth modes for a Group IV metal such as Sn, where we expect more intermixing of the tetravalent Sn and Si atoms. Our STM studies show that, unlike for the noble metals, Sn forms adsorbed dimers on the Si(5 5 12) surface at low coverage (< 0.5 ML) and moderate annealing temperatures (~450C). These dimers appear as bright protrusions in the trenches between Si rows, and in fact intermix with existing Si dimers on the surface. At higher coverages, Sn forms relatively large protrusions with a 4x periodicity along the underlying Si tetramer rows. Such strongly corrugated features have never been observed for the deposition of noble metals, indicating a significantly different growth behavior for this group-IV metal. As the coverage is increased (>1 ML), Sn creates a disordered surface with only remnants of the row-like surface morphology remaining. At higher annealing temperatures (700C+), however, the surface undergoes a large-scale rearrangement with sawtooth facets being formed. We are presently exploring the optimal conditions to produce such sawtooths, because such a corrugated surface provides yet another interesting template for growth. @FootnoteText@ @footnote 1@ K. M. Jones, K. M. Saoud, and A. A. Baski, Cluster and Nanostructure Interfaces, edited by P. Jena (World Scientific, New York, 2000), p. 49-54, in press.