| AVS 54th International Symposium | |
| Surface Science | Monday Sessions |
| Session SS2-MoM |
| Session: | Surface Structure, Growth, and Etching of Silicon and Germanium |
| Presenter: | N.T. Kinahan, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) & Trinity College Dublin, Ireland |
| Authors: | N.T. Kinahan, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) & Trinity College Dublin, Ireland D.E. Meehan, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) & Trinity College Dublin, Ireland T. Narushima, National Institutes of Natural Sciences, Japan K. Miki, National Institutes of Natural Sciences, Japan J.J. Boland, CRANN & Trinity College Dublin, Ireland |
| Correspondent: | Click to Email |
The oxidation of silicon surfaces has been widely studied due to its scientific and technological importance. However, despite extensive experimental and theoretical studies, the details of the oxidation reaction are not yet fully understood. It has recently been suggested that surface stress measurements may prove useful in elucidating this and related issues. In the case of adsorption on solid-state surfaces, stress arises primarily from differences in atomic size and electronegativity, in addition to unit cell expansion due to the incorporation of atoms into the substrate. Here, we study the surface stress evolution encountered during oxidation of the Si(111)-7x7 surface using a novel system combining both surface stress measurement and scanning tunnelling microscopy (STM) capabilities.1,2 The former measurement is based on the displacement of a large silicon cantilever sample, while the latter measurement permits direct observation of the atomic structure of the same cantilever sample. We show that the initial oxidation of the Si(111)-7×7 surface at room temperature involves two compressive stress stages with different growth signatures. The atomic scale origins of the measured surface stress evolution will be discussed and supported via complementary STM data. In particular, we demonstrate that the initial rapid rise in compressive stress is associated with selective oxidation of the faulted-half units of the 7x7 reconstruction.
1 T. Narushima, N.T. Kinahan, J. J. Boland, Rev. Sci. Instrum. 76 095113 (2005).
2 T. Narushima, N.T. Kinahan, J. J. Boland, Rev. Sci. Instrum. 78 053903 (2007).