Almost all theoretical studies on pattern formation on ion-sputtered surfaces are based on Sigmund's theory of sputtering [1]. Sigmund developed a kinetic theory, in which with assumption of random slowing down of ions, a solution for Boltzmann equation is provided. This solution, which describes the distribution of particles in the kinetic phase space, can be approximated by a Gaussian under certain conditions. However, Binary Collision Approximation (BCA) computer simulations show that these approximations fail especially for near-grazing incidence angles [2].

Here, in contrast to the previous works, we implement the results of BCA simulations directly in a previously examined discrete kinetic Monte Carlo model [3], and compare the pattern formation to the classic case of Gaussian distribution. Patterns topology, sputtering yield, and surface roughness are the main investigated items. We conclude that simulations based on BCA provide more realistic results and for more precise studies, the Gaussian distribution should be replaced by a more accurate one.

[1] P. Sigmund, Phys. Rev. 184(2) (1969) 383-416.
[2] M. Feix, A.K. Hartmann, R. Kree, J. Muñoz-García, and R. Cuerno, Phys. Rev. B 71(12) (2005) 125407.
[3] A.K. Hartmann, R. Kree, and T. Yasseri, J. Phys. 21 (2009) 224015.

Taha Yasseri*, Institute of Theoretical Physics - University of Goettingen, Germany
Reiner Kree, Institute of Theoretical Physics - University of Goettingen, Germany

*presenting author