On the Shift of the Maximum of the Polar Angular Distribution of Sputtered Atoms in the MD Model of the (001) Ni Face Sputtering

Using an up-to-date full molecular dynamics model of sputtering of single crystals and taking into account the incidence of ions on the surface, the peculiarities and mechanisms of atom sputtering during bombardment of the (001) Ni face with 200 eV Ar ions are studied for two target temperatures. It is shown for the first time that with an increase in the energy of sputtered atoms not only the maximum of their polar angular distribution in the azimuthal direction toward the Wehner spots but also the maximum of the polar angular distribution integrated over the azimuthal angles shifts first toward the normal to the surface and then in the opposite direction. The polar distribution integrated over the azimuthal angles is formed by atoms ejecting from the surface at much larger polar angles than that in the final (observed) distribution. Both effects are explained in terms of the surface mechanism of single crystal sputtering.