The molecular dynamics technique was used to study defect production, mean square atomic displacements, the jumping of atoms to other layers and sputtering yields during the development of a collision cascade in a crystal (containing Al impurity atoms) under 100eV Ar-ion bombardment at 300K. The resultant collision cascade functions for atomic jumps were used to calculate the mean drift velocities of recoils and mixing coefficients, which exhibited oscillations with depth. By using these results, the mixing equation in the diffusion approximation was solved for the case of a dilute Al marker in a Ni crystal under ion bombardment, and yielded the Al surface concentration depth profile during sputtering. A preferential sputtering of Al was observed, which had a marked effect upon the calculated depth profile. Differences in the properties of Al and Ni atoms produced an additional impurity convective flux which was not present in 1-component systems. This additional flux caused an increase in the Al surface concentration during depth profiling.

Molecular Dynamics Simulation of Mass Transport Processes in a Ni Crystal with Al Atoms as Impurity under Low Energy Ion Bombardment. G.V.Kornich, G.Betz, A.I.Bazhin: Nuclear Instruments and Methods in Physics Research B, 2001, 173[4], 417-26