ELECTRON-ENERGY LOSS MEASUREMENTS OF IN/SI(111) SUPERSTRUCTURES - CORRELATION OF THE SPECTRA WITH SURFACE SUPERSTRUCTURES

The electron energy loss spectral change of In/Si(111) superstructures was measured while increasing the indium coverage in small steps. By measuring the loss spectra of these superstructured In/ Si(111) surfaces, it was found that each superstructure has a characteristic loss spectrum and the shape of the loss spectrum changes drastically only at the transition region between two superstructures. In the energy loss spectral change, the energy shift of the overlayer plasmon at the phase transition between two superstructures is outstanding. This shift is caused by the change of the depolarization effect which reflects the special atomic arrangement of each superstructure.