Noncontact atomic force microscopy (NC-AFM) was applied to investigating the creation of monatomic depth rectangular pits, the growth of metals, and the templated growth of molecules on the KBr (001) surface under ultrahigh vacuum conditions. The pits were produced by a new method where the sample is exposed to a controlled dose of charge from an electron beam evaporator. The structure and size distribution of the pits was characterized by NC-AFM. For the metal growth studies, gold, tantalum, and palladium were deposited onto KBr by electron beam deposition. The gold produced tall multiply twinned and epitaxial nanoparticles, while the tantalum formed flatter fractal islands. The palladium growth resulted in the creation of rectangular KBr islands in addition to palladium nanoparticles. Despite the use of a charge deviating grid, charge played an important role during the metal growth. In particular, the number density of gold nanoparticles followed nearly the same temperature dependence as the pits, suggesting that the metal nanoparticles nucleate predominantly at defect sites created by incident charge. The effect of charge was also seen in the tantalum system where pits surrounded the nanoparticles prepared at elevated temperatures. By creating pits before depositing gold, it was shown that the pits edges can be used to template the growth of metals. It was also shown that the pits can be used to trap PTCDA molecules and to align C60 molecules with the <100> direction of the substrate. Molecular resolution NC-AFM measurements were used to determine the structures and lattice constants of the molecular nanostructures. Experiments involving the sequential growth of metals and molecules showed that the order of deposition and the strength of the molecule-metal interaction are key factors in determining the nature of the growth. Furthermore, it was shown that metal structures can be used to nucleate the growth of sufficiently strongly interacting molecules.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.102682 |
| Date | January 2006 |
| Creators | Mativetsky, Jeffrey M. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Physics.) |
| Rights | © Jeffrey M. Mativetsky, 2006 |
| Relation | alephsysno: 002573180, proquestno: AAINR27819, Theses scanned by UMI/ProQuest. |
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