6533b7d8fe1ef96bd1269793

RESEARCH PRODUCT

Reflection high energy electron diffraction as a tool in cluster deposition experiments

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Reflection high energy electron diffraction (RHEED) is used to study the structure and orientation of mass-filtered iron clusters upon deposition ontoW(110). The present setup enables in situ investigations during deposition and thermal annealing. Particles as small as 2 nm at low density on the surface can be studied. The experiments reveal that larger particles with a diameter of about 13 nm are randomly oriented on the substrate with a preferred tendency to rest on their surface facets. Thermal annealing leads to a partial realignment and a significant flattening of the particles. In contrast 2 nm particles are found to align spontaneously in an epitaxial manner on W(110). Thermodynamic arguments suggest that thermally activated motion of dislocations is responsible for the observed alignment phenomena rather than temporary melting of the particles. RHEED setup for in situ investigations in cluster deposition experiments.