High atom density in the ‘‘1×1’’ phase and origin of the metastable reconstructions on Si(111)

Publisher Website
Google Scholar
Abstract
We report unambiguous atomic scale evidence demonstrating that the atom density in the ‘‘1×1’’ high temperature phase of Si(111) is ∼6% higher than the 7×7. Such evidence is provided by scanning tunneling microscopy observation of excess adatom density and related island formation on surfaces prepared by a novel method which provides a low step density. The presence of the excess adatom density is also correlated to the observation of areas of metastable reconstructions, i.e., 9×9, 2×2, c2×4, and √3 × √3 , much larger than previously reported and for the first time, the existence of metastable 11×11 on Si(111).