Growth of Ag rows on Si(5512)

Our scanning tunneling microscopy studies show that Ag deposited: onto Si(5 5 12) and annealed to moderate temperatures (400-450 degrees C) forms well -ordered overlayer rows. These rows have aspect ratios up to 150:1 and ther efore are possible candidates as "nanowires." es' the Ag coverage is increa sed, the rows grow in length and number until the surface forms a periodic array of:such structures at similar to 0.25 monolayer (ML). A statistical a nalysis of these rows reveals a linear increase in median row length as a f unction of coverage with a median length of 67 nm at full coverage (similar to 0.25 ML). At higher annealing temperatures (>500 degrees C) Ag continue s to-form row-like structures, but the rows are wider and cause local facet ing of the underlying Si substrate. We can therefore conclude that the lowe r temperature Ag rows are actually a metastable arrangement of the surface. (C) 1999 American Vacuum Society. [S0734-2101(99)06004-2].