Abstract
Scanning tunneling microscopy has been used to examine growth mode of Al on a Si (111) (√3×√3) -Alsurface at room temperature. It is found that submonolayer deposition leads to formation of tiny 2 dimensional (2D) nuclei of Al. These nuclei are uniformly distributed over Si (111) (√3×√3) -Al terraces. When increasing a coverage of 5 monolayers, tiny Al 2D nuclei coalesce to form large Al islands with atomically flat (111) surfaces. We will discuss the difference in growth mode in terms of Al diffusion length.
