Enhanced sputtering from nanoparticles and thin films: Size effects

Abstract

Sputtering of gold nanoparticles and nanometer-thin films under 25 keV gallium-ion bombardment is shown, using molecular-dynamics simulations, to be significantly enhanced compared to bulk. The highest yield, about three times that of bulk gold, occurs for particles of about 8 nm in diameter. For thin films, the maximal yield is obtained for roughly 3 nm thick films. A model based on the work of Sigmund is presented to explain the size-dependence.