Au sputtering by cluster bombardment: A molecular dynamics study

Sputtering of a Au (1 1 1) surface induced by Au, cluster bombardment is st udied by molecular dynamics simulation, aiming at statistically representat ive results for larger clusters. Both equi-velocity Au-n (n = 1, 2, 4) clus ters at energy E/n = 16 keV/atom and equi-energy clusters (n = 1, 2, 4, 8, 12) with E = 16 keV are used as projectiles. We observe: huge sputter yield s, displaying a strong dependence on cluster size and energy; late sputter emission (beyond 30 ps after cluster impact); an increasing percentage of s puttered clusters for large sputter yields; the formation of large craters; a narrowing of the sputter-yield distributions for large clusters. In a se nsitivity study, we show that the equilibrium interatomic potential has a s trong influence on the sputter yield. (C) 2000 Elsevier Science B.V. All ri ghts reserved.