Sputtering at grazing ion incidence: Influence of adatom islands

Abstract

When energetic ions impinge at grazing incidence onto an atomically flat terrace, they will not sputter. However, when adatom islands ͑containing N atoms͒ are deposited on the surface, they induce sputtering. We investigate this effect for the specific case of 83°-incident 5 keV Ar ions on a Pt ͑111͒ surface by means of molecular-dynamics simulation and experiment. We find that-for constant coverage ⌰-the sputter yield has a maximum at island sizes of N Х 10-20. A detailed picture explaining the decline of the sputter yield toward larger and smaller island sizes is worked out. Our simulation results are compared with dedicated sputtering experiments, in which a coverage of ⌰ = 0.09 of Pt adatoms are deposited onto the Pt ͑111͒ surface and form islands with a broad distribution around a most probable size of N Х 20.

News on sputter theory: Molecular targets, nanoparticle desorption, rough surfaces

“…While keeping our discussion rather general, we will illustrate the presentation with results obtained for the specific case of 5 keV Ar incidence on the Pt(1 1 1) surface, which has been analyzed in great detail in the recent past [28][29][30][31][32][33][34][35][36][37][38][39]. Let us consider a situation where a flat surface terrace reflects the bombarding ion beam such that the sputter yield is zero.…”

“…Other surface defects, like single adatoms or adatom islands, may be analyzed in a way analogous to that of surface steps [36,39]. Fig.…”

Subsurface channeling of keV ions between graphene layers: Molecular dynamics simulation

“…Glancing ion incidence on metals has been studied in considerably greater detail, both by experiment and by simulation [5][6][7][8][9][10][11]. Such glancing impact gives rise to the phenomenon of subsurface channeling where the projectile is channeled immediately under the surface.…”