Large-scale atomistic calculations, using empirical potentials for modelingsemiconductors, have been performed on a stressed system with linear surfacedefects like steps. Although the elastic limits of systems with surface defectsremain close to the theoretical strength, the results show that these defectsweaken the atomic structure, initializing plastic deformations, in particulardislocations. The character of the dislocation nucleated can be predictedconsidering both the resolved shear stress related to the applied stressorientation and the Peierls stress. At low temperature, only glide events inthe shuffle set planes are observed. Then they progressively disappear and arereplaced by amorphization/melting zones at a temperature higher than 900 K.
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