Electron energy-loss spectroscopy study of amorphization process of graphite bombarded with hydrogen ions and energetic electrons at low temperatures.

Structural change of graphite bombarded with hydrogen ions as well as energetic electrons is investigated mainly by the EELS (electron energy-loss spectroscopy) technique, with a focus on the formation of diamond-like amorphous (DLA) phase at low temperatures. The chemical effects of hydrogen ions on the amorphization process are examined by comparing the results obtained by hydrogen-ion bombardment with those obtained by electron bombardment. The critical temperatures for the formation of DLA phase during hydrogen-ion and electron bombardments are determined. Finally, a model of the amorphization process of graphite during ion-bombardment is presented.