Abstract
Low energy electron microscopy images of Si(111) surfaces during submonolayer deposition of Co or Ni at temperatures near 700° C reveal a phase separation into a disordered "ring cluster" phase and the ordered 7 × 7 reconstruction. For Co/Si(111) we find that temperature-driven phase separations at a fixed dose are reversible and occur at a fixed surface coverage. The shape of the phase boundary reveals a repulsive interaction between Co-containing ring clusters in the disordered phase. For Ni/Si(111), dissolution into the bulk prevents reversible separations between surface phases. At coverages close to 1/7 ML an ordered close-packed √7 × √7 ring cluster phase forms for Co/Si(111), but not for Ni/Si(111). The √7 × √7 phase disappears irreversibly on heating, due to the nucleation and growth of stable silicide islands.
Original language | English (US) |
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Pages (from-to) | 1179-1188 |
Number of pages | 10 |
Journal | Surface Review and Letters |
Volume | 5 |
Issue number | 6 |
DOIs | |
State | Published - Jan 1 1998 |
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry