First LEEM results from the University of Illinois at Urbana-Champaign depict a an 830-Å-thick niobium film grown at 900 °C on epitaxial grade (11-20) sapphire substrate. The sample was prepared ex situ by Brian Wiemeyer and Randy Appleton in an MBE chamber. It was subsequently annealed in LEEM at 1400 °C. The LEEM experiments were performed by Dr. W. Swiech and Professor C.P. Flynn. Upper left is the low-energy electron diffraction (LEED) pattern taken at energy of 29 eV. The image shows that the bcc Nb film is epitaxial in the (110) orientation. Circled spots on the upper right pattern (taken at 13 eV) were chosen to make the two dark field images shown below.

These images show two complementary domains that decorate the step edges (lines) and also occur as oriented regions on the terraces. Micrographs were taken at room temperature at energy of 7 eV. Field of view: approx. 4 µm². (August 1997).

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