Acquisition of an Advanced Surface Microscopy Facility

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9512231 Chiang An advanced surface microscopy facility, consisting of an ultrahigh vacuum low energy electron microscope (LEEM) and a ultrahigh vacuum scanning tunneling microscope (STM) installed within the same vacuum system with sample transfer between the two instruments, will be established. The combination of the two instruments, LEEM and STM, within the same ultrahigh vacuum environment will enable the structural study of the surfaces of materials with both atomic resolution (STM) and in real time (LEEM). Both microscopes will permit control of the sample temperature during imaging and deposition of metals and adsorbates. The facility will be used by eleven investigators and their research groups to study surface properties in several key areas. These include: (1) dynamics of surface structural changes, such as nucleation and growth of metal, semiconductor, and oxide overlayers; (2) structural effects on adsorbates, such as segregation, diffusion, and reactivity; (3) synthesis and characterization of nanoscale materials, such as quantum dots, thin-film fullerene polymers, and nanoclusters. %%% Two complementary types of surface microscopes, a low energy electron microscope and a scanning tunneling microscope, will be utilized to probe surface systems with varying spatial and time resolution as a function of important parameters such as temperature and coverage of adsorbates. The possibility exists to image an important class of catalysts and simultaneously investigate their reactivities and catalytic properties. ***