Electron energy-loss spectroscopy and energy-filtered imaging of C60 thin films

Electron energy-loss spectra and energy filtered images have been obtained from C-60 film deposited on Si(100) substrate using a serial electron energy loss spectrometer equipped on a scanning transmission electron microscope. The electron energy loss spectra of the specimen in the low loss region reveals the plasmon energies of C-60 to be 6.6 eV and 25.3 eV. Energy-filtered images obtained at energy-losses corresponding to zero-loss, plasmon energies of Si and C-60 and core loss energies of Si and C-60 clearly demonstrate the elemental mapping capabilities of the energy-filtered imaging technique. Energy-filtered selected area diffraction pattern indicates that the film is amorphous, i.e., the C-60 molecules are randomly arranged on the Si substrate, with a mean intermolecular spacing of 9.9 +/- 0.2 Angstrom.