Nanocluster Ions and Beam Techniques for Material Modification

Various kinds of clusters such as hydrogen, ionic, and metallic bonding clusters were generated using several unique methods such as the nozzle beam, high-electric-field, and evaporation-on-liquid methods. The size and structure of these clusters were analyzed by time-of-flight (TOF), high-energy electron diffraction (HEED), transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS). In addition, the impact of the cluster ions on a solid surface was investigated, and unique irradiation effects were found, such as the low-energy irradiation effect and the high-density irradiation effect. The kinetic energy of the cluster ion was converted to thermal energy, resulting in extremely high temperatures. Furthermore, the simultaneous use of chemical sputtering and thermal annealing processes was demonstrated with ethanol cluster ion beams. As a result, low irradiation damage and high-rate sputtering of Si surfaces was performed by the retardation potential method.