Potential and Kinetic Sputtering of UO2 by Slow Highly Charged Ions

First measurements of angular distributions of Uranium dioxide (UO2) sputtering induced by slow highly charged Xenon ions (81 keV, v < 0.16 a.u.) have been performed using a catcher technique. The angular distributions are found to be non-isotropic. A clear projectile charge state effect on the sputtering process is observed. From the angular distributions, the total sputtering yield can be deduced. It increases with the projectile potential energy. Varying the projectile incidence angle from 0° with respect to the surface normal to 60°, the sputtering yield increases in the beam forward direction. The projectile charge effect on the angular distribution becomes less prominent at 60° than at 0°. In addition, angular sputtering distributions were studied with Xe25+ at 8 keV (v < 0.02 a.u.), where the potential and kinetic energies of the projectile are equal.