Desorption of cluster ions from solid Ne by low-energy ion impact

We investigated Ne(+) ions and Ne(n)(+) (n = 2-20) cluster ions desorbed from the surface of solid Ne by 1.0 keV Ar(+) ion impact. Kinetic energy analysis shows a considerably narrower energy distribution for Ne(n)(+) (n >= 3) ions than for Ne(n)(+) (n = 1, 2) ions. The dependence of ion yields on Ne film thickness indicates that cluster ions (n >= 3) are desorbed only from relatively thick films. We conclude that desorbed ions grow into large cluster ions during the outflow of deep bulk atoms to the vacuum