STM and STS studies of terraces on Si(5 5 12) surface with Ag atom adsorption

Summary form only given. The stable high-index Si(5 5 12) surface recently attracts much attention due to its potential application. Since the reconstructed Si(5 5 12)-2/spl times/1 has terraces of a single atomic plane with row-like symmetric structure, it can be a superior template to grow one-dimensional nano-scale wires though depositing noble metals, like Ag or Au, on the reconstructed Si(5 5 12)-2/spl times/1 surface. This technique is suitable for the device fabrication process. Hence, the terraces are usually expected to be large and regular for making 1-D nanowires with high aspect ratio. However, steps and kinks always appeared on the reconstructed surface. The terraces are separated by these steps then became small and not uniform because the kinks formed. In the present study, we observed different terraces on the reconstructed Si(5 5 12)-2/spl times/1 surfaces with Ag atom adsorption at various coverages, or in various pressures during Ag deposition using UHV-STM. It was found that when samples annealed at the same condition, the width of terraces was larger for the sample with the higher Ag coverage, or for the sample performed Ag deposition in higher pressure. If Ag atoms nucleated and formed clusters on the surfaces, they preferentially diffused to step edges along the terraces and adsorbed on kink sites, limiting step movements and terrace sizes.