Dewetting and nanopattern formation of thin Pt films on SiO2 induced by ion beam irradiation

Dewetting and nanopattern formation of 3-10 nm Pt thin films upon ion irrad iation is studied using scanning electron microscopy (SEM). Lateral feature size and the fraction of exposed surface area are extracted from SEM image s and analyzed as functions of ion dose. The dewetting phenomenon has littl e temperature dependence for 3 nm Pt films irradiated by 800 keV Kr+ at tem peratures ranging from 80 to 823 K. At 893 K, the films dewet without irrad iation, and no pattern formation is observed even after irradiation. The th ickness of the Pt films, in the range 3-10 nm, influences the pattern forma tion, with the lateral feature size increasing approximately linearly with film thickness. The effect of different ion species and energies on the dew etting process is also investigated using 800 keV Kr+ and Ar+ irradiation a nd 19.5 keV He+, Ar+, Kr+, and Xe+ irradiation. The lateral feature size an d exposed surface fraction scale with energy deposition density (J/cm(2)) f or all conditions except 19.5 keV Xe+ irradiation. (C) 2001 American Instit ute of Physics.