X-ray standing wave study of the Sr/Si(001)-(2 3) surface
نویسندگان
چکیده
Sub-monolayer surface phases of Sr on Si(0 0 1) have been studied with low-energy electron diffraction (LEED) and X-ray standing waves (XSW). A (3 · 1) phase was observed after depositing 0.6–0.8 ML Sr on room-temperature Si(0 0 1). Annealing at 750–800 C caused a portion of the Sr to desorb and resulted in a sharp (2 · 3) LEED pattern. Normal Si(0 0 4) and off-normal Si(0 2 2) and Si(1 1 1) XSW measurements made on the (2 · 3) phase indicate that Sr atoms must sit at either cave or bridge sites. The XSW results also suggest that if a sufficiently low anneal temperature is used, the (2 · 3) phase co-exists with short-range ordered regions of Sr atoms located at valley-bridge sites. 2003 Elsevier B.V. All rights reserved.
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