Superior regularity in erosion patterns by planar subsurface channeling.
The onset of pattern formation through exposure of Pt(111) with 5 keV Ar(+) ions at grazing incidence has been studied at 550 K by scanning tunneling microscopy and is supplemented by molecular-dynamics simulations of single ion impacts. A consistent description of pattern formation in terms of atomic scale mechanisms is given. Most surprisingly, pattern formation depends crucially on the angle of incidence of the ions. As soon as this angle allows subsurface channeling of the ions, pattern regularity and alignment with respect to the ion beam greatly improves. These effects are traced back to the positionally aligned formation of vacancy islands through the damage created by the ions at dechanneling locations.
Redinger
Alex
A
I. Physikalisches Institut, RWTH Aachen, 52056 Aachen, Germany.
Hansen
Henri
H
Linke
Udo
U
Rosandi
Yudi
Y
Urbassek
Herbert M
HM
Michely
Thomas
T