| AVS 56th International Symposium & Exhibition | |
| In Situ Microscopy and Spectroscopy: Interfacial and Nanoscale Science Topical Conference | Friday Sessions |
| Session IS+AS-FrM |
| Session: | In-Situ Microscopy and Spectroscopy: Dynamic Nanoscale Processes |
| Presenter: | N. Ferralis, University of California, Berkeley |
| Authors: | N. Ferralis, University of California, Berkeley F. El Gabaly, Sandia National Laboratories A.K. Schmid, Lawrence Berkeley National Laboratory R. Maboudian, University of California, Berkeley C. Carraro, University of California, Berkeley |
| Correspondent: | Click to Email |
The spreading dynamics of a bilayer gold film propagating outward from gold clusters, which are pinned to the clean Si(111) surface, are imaged in real time using low energy electron microscopy. By monitoring the morphological evolution of the Au-Si interface at fixed temperature, a linear dependence of the spreading radius of the interface as function of time is found. The measured spreading velocities in the temperature range of 800 < T < 930 K varies from below 100 pm/s to 50 nm/s. We show that the linear time dependence in the formation of the interface between the gold silicide and the clean Si surface is a direct consequence of the large difference in surface energy between the two phases. In atomistic terms, the dynamics of the spreading is reaction-attachment limited, and it appears to be regulated by the structural reconstruction of gold silicide that that takes place at the interface.