Interaction between the 30° partial dislocation and hex-vacancy in silicon

摘要

The molecular dynamics (MD) method is used to investigate the interaction between the 30° partial dislocation and hex-vacancy (V _6) in Si. The interaction processes are described in detail and compared with the prior results of mono-vacancy (V _1) and di-vacancy (V _2). It is found that dislocations are pinned by V _6 when the shear stresses are smaller than a definite critical value τ _c. It illustrates that the encountered two segments beside vacant sites parallel each other or annihilate. Moreover, it is shown that the critical shear stress τ _c is mainly determined by both the migration barrier of kink and the volume of vacancy. Although V _6 cannot make dislocations move faster due to the present small models, it may lower the dislocation density in certain conditions due to the pinning effect.