| AVS 57th International Symposium & Exhibition | |
| Surface Science | Monday Sessions |
| Session SS2-MoA |
| Session: | Stress and Bonding Energetics in Nucleation and Growth |
| Presenter: | C. Mullet, University of California, Davis |
| Authors: | C. Mullet, University of California, Davis S. Chiang, University of California, Davis |
| Correspondent: | Click to Email |
We studied Ag island growth on reconstructed Ge(110) and Ge(111) surfaces with low energy electron microscopy (LEEM). At 480 C, one-dimensional (1D) island growth was observed on Ge(110). Island nucleation proceeds from defects in the Ge substrate, with island thickness corresponding to the size of the substrate defect where the island nucleation occurred. As Ag is deposited, islands lengthen but do not thicken. At 9 ML, Ag coverage islands were up to 10 µm long, and thicknesses varied from 100 nm to 250 nm. One-dimensional islands were also produced by Ag deposition at room temperature followed by sample heating. Round Ag islands resolvable in LEEM were observed and coalesced into many long 1D islands as temperature was increased. Islands formed by deposition at room temperature followed by heating to a particular temperature were shorter and thicker than islands grown by deposition on a substrate held at that same temperature. Ag growth on Ge(111) is Stranski-Krastanov. Multilayer Ag island formation begins after the Ag (√3x√3)R30° phase completes at one monolayer. Ag islands exhibit hexagonal faceting. For both the Ge(111) and Ge(110) surfaces, Ag islands induce changes in the Ge substrate that leave a “footprint” observable in LEEM after all Ag has been desorbed from the surface.
*Funding from NSF CHE-0719504; NSF PHY-0649297 (REU)