• Alkali Metals
• Semiconductors
• Silicon
• Surface reconstructions

In this thesis, I report a wide investigation on the interaction and induced reconstructions by Rb on the Si(111)-(7 × 7) surface. By tuning parameters of the induced surface reconstructions, a better and more detailed understanding of the Rb/Si(111) system has been gained.
Sample analysis via Low Energy Electron Diffraction allowed to observe for the first time a Rb/Si(111)-(6 × 1) reconstruction. Moreover, the Low Energy Electron Diffraction analysis allowed to obtain a fast characterization of the samples as well as qualitative information on the surface induced modifications and its periodicity. The use of Scanning Tunneling Microscopy allowed to obtain the first real space characterization of the Rb/Si(111)-(3 × 1) surface. Scanning Tunneling Microscopy provided a direct and local information on the surface arrangement as well as further insights on the interaction between Si and Rb atoms and on the film growth dynamics. On the other hand, Scanning Tunneling Spectroscopy has provided some insight on the electronic structure of the system.
This entire work has been realized at the facilities of Laboratorio NEST. Samples preparation as well as their characterization, done via low energy electron diffraction (LEED) and scanning tunneling microscopy and spectroscopy (STM and STS), have been performed in an Ultra-High Vacuum environment (UHV chamber of a RHK Technology STM).