Effect of misfit dislocation on surface diffusion
Abstract
We apply molecular dynamics and molecular static methods to study the effect of misfit dislocations on adatom diffusion in close proximity to the dislocation core in heteroepitaxial systems, using many-body interaction potentials. Our system consists of several layers (three-seven) of Cu on top of a Ni(111) substrate. The misfit dislocations are created with the core located at the interface between the Cu film and the Ni substrate, using the repulsive biased potential method described earlier. We find that presence of the defect under the surface strongly affects the adatom trajectory, creating anisotropy in atomic diffusion, independent of the thickness of the Cu film. We also calculate the potential energy surface available to the adatom and compare the energy barriers for adatom diffusion in the proximity of the core region and on the defect-free surface.
- Publication:
-
Physical Review B
- Pub Date:
- July 2011
- DOI:
- 10.1103/PhysRevB.84.035455
- Bibcode:
- 2011PhRvB..84c5455A
- Keywords:
-
- 68.35.Fx;
- 68.43.Jk;
- 68.55.Ln;
- 68.37.-d;
- Diffusion;
- interface formation;
- Diffusion of adsorbates kinetics of coarsening and aggregation;
- Defects and impurities: doping implantation distribution concentration etc.;
- Microscopy of surfaces interfaces and thin films