| AVS 58th Annual International Symposium and Exhibition | |
| Surface Science Division | Wednesday Sessions |
| Session SS1-WeM |
| Session: | Atomistic Control of Structure & Evolution |
| Presenter: | Jun Nogami, University of Toronto, Canada |
| Authors: | N. To, University of Toronto, Canada S. Dobrin, University of Toronto, Canada J. Nogami, University of Toronto, Canada |
| Correspondent: | Click to Email |
A self-aligning nanostencil mask was used to pattern circular features of tin and indium on an atomically clean Si(001) substrate. The shadow mask limited material deposition to below where the membrane was open, leaving adjacent areas of clean surface for material to diffuse. STM was used to study the room temperature surface diffusion of these metals in UHV and DFT was used to calculate relevant activation barriers. The comparison of these two metals is significant since they have the same atomic structure in the first atomic layer when grown on Si(001). The diffusion of tin is limited in comparison with indium, and remains so even at increasing metal coverage. Indium forms unstable 3D islands that dissolve over time and contribute to the spreading of a single atomic layer thick film on the surrounding clean surface. The difference in behavior between the two metals can be attributed to the energy balance between 3D islands and the 2D wetting layers, as well as differences in activation energy for diffusion of atoms on top of the first atomic layer of metal. These results also show the potential for stencil patterning to provide insight into aspects of thin film growth.