Dislocation climbing in a three-layer structure

The introduction by climbing of an edge dislocation from the free-surface of a three-layer structure has been first investigated from an energy-based calculation. The activation energy and unstable equilibrium positions of the dislocation have been thus determined versus the misfit parameter. Likewise, the critical strain required for the dislocation introduction in the matrix-layer interface has been characterized. The introduction by climbing of a second dislocation has been then considered. The energy barrier, stable and unstable positions have been again calculated for the second dislocation considering the firstly introduced dislocation is lying in the interface closer to the free-surface. A stability diagram with respect to the introduction of the two dislocations is finally displayed versus the misfit parameter.