Sputtering of Ag under C60þ and Gaþ projectile bombardment

Cluster ion bombardment often results in large secondary ion yield enhancements relative to atomic ion bombardment. The yields of neutral particles and secondary ions sputtered from a silver surface were investigated through experiments and molecular dynamics (MD) computer simulations. The results show that the neutral Ag yield produced by 15 keV C60þ bombardment is 5.6-fold higher than that found for 15 keV Gaþ bombardment, which is in agreement with simulations. The enhancement effect is observed to be about the same for both neutral species and their corresponding secondary ions. Experimental results also indicate that the Ag neutral species produced by C60þ bombardment have emission velocity distributions that maximize at much lower values than those observed by Gaþ bombardment, suggesting the presence of non-linear collision cascades. # 2004 Elsevier B.V. All rights reserved.