9521392 Williams The phenomena of nucleation and growth of metals and metalloid islands (Ni, Ag, In, Sn, Sb, and Te), on semiconductor surfaces (Si) will be investigated. Techniques of Time-of Flight Low Energy Ion Scattering will be used to measure the coverage of the surface islands during material deposition to obtain kinetic information. Scanning Tunneling Microscopy (STM) will provide spatial information such as shape, size and densities of the islands, which can be related to thermodynamic properties of the system. The experimental data will be compared with computer simulations to determine growth mechanisms and physical parameters, especially surface diffusion constants and line tensions for different adsorbates. Materials with a broad range of properties and behaviors have been selected. STM will also provide information on the size dependence of the electronic property of the islands and the unique properties of supported clusters. %%% The ultimate objective in this research is to understand the kinetic and thermodynamic processes of nucleation and growth so that the formation of an optimized structure of dots, lines, and/or planes can be guided through control of deposition parameters such as flux, fluence and substrate temperature. The selected Materials have a broad range of properties and behaviors. Techniques of Time-of Flight Low Energy Ion Scattering will provide information on the coverage of the surface islands during material deposition to obtain kinetic information. Scanning Tunneling Microscopy (STM) will be used to study spatial information such as shape, size and densities of the islands, which can be related to thermodynamic properties of the system. The experimental data will be compared with computer simulations data to determine growth mechanisms and physical parameters, especially surface diffusion constants and line tensions for different adsorbates STM will also p rovide information on the size dependence of the electronic property of the islands and the unique properties of supported clusters. ***
