Preparation and Observation of Si sub (10) Clusters on Au(001) - (5x20).

Size-selected Si sub(10) clusters have been deposited on a clean Au(001)-(5x20) surface and imaged using a scanning tunneling microscope in UHV. Many clusters appeared roughly triangular in 2-D projection, lending support to previously proposed models for Si sub 10. From tunneling spectroscopy measurements, the clusters were found to have a band gap 0.95~1.15 eV wide. The results indicate that electron density is transferred from the Au substrate to the clusters, and for some clusters long range screening was observed on the substrate.