Shape Transition and Dislocation Nucleation in Strained Epitaxial Islands

Equilibrium shape and dislocation nucleation in strained epitaxial nanoislands

Dislocation Energetics in Epitaxial Strained Islands

We calculate (to rst order in the Burgers vector) the energy of introducing dislocations into Stranski-Krastanow islands having equilibrium shape. These results suggest that misst dislocations of diierent Burgers vector tend to segregate spatially within the islands, which may aaect the mosaic structure of lms formed by island coalescence.

Mechanisms of Dislocation Nucleation in Strained Epitaxial Layers

Using molecular static simulations we have studied possible mechanisms of stress relaxation with misfit dislocation nucleation in strained heteroepitaxial layers. Two-dimensional models of atomic systems with Lennard-Jones type potential were considered. Combination of total energy minimization with spherical repulsion and nudged elastic band calculation allowed us to study possible transitions...

Surface Instability and Dislocation Nucleation in Strained Epitaxial Layers

We have studied numerically the stability and defect nucleation in epitaxial layers on a substrate with lattice mismatch. Stress relaxation and energy barriers for mis t dislocation nucleation are estimated using modern methods for saddle point search based on a combination of activation with local repulsive potential and the Nudged Elastic Band method. Stress relaxation processes correspond to...

Step-flow growth on strained surfaces

A theoretical study is presented of the effect of misfit strain on the transition from step flow to island nucleation dominated epitaxial layer growth on a vicinal surface. The analysis generalizes a set of reaction-diffusion equations used for homoepitaxy to include the fact that heteroepitaxial strain changes the Arrhenius barrier for diffusion and promotes the detachment of atoms from the ed...