Ion Sputtering of Solid Surfaces

  The animation below shows a Molecular Dynamics computer simulation of the elastic collisions and their consequences when an Argon ion of 5 keV kinetic energy (red) hits the (111) surface of a silver single crystal under normal incidence. The different snapshot images are separated by a time interval of 200 femtoseconds. The particular trajectory shown represents one of the large events, where many atoms are sputtered. When averaged over many different trajectories (corresponding to different impact points on the surface), the average number of sputtered atoms under these conditions amounts to approximately eight. From this single trajectory, a number of observations can be made which are characteristic of the sputtering process :

5 keV Ar -----  Ag (111)