Dislocation boundary interactions in a Σ13 grain boundary in silicon. II. Grain boundary structures and dislocations produced during deformation

Abstract

Abstract A Σ13, 22·6°/[001]½, grain boundary in Si with plastically deformed at 850°C under a range of loading orientations and strains. The resulting deformation was characterized in the transmission electron microscope, including the determination of the operating slip systems, and the Burgers vectors of the various grain boundary dislocations produced. For small strains, the observed grain boundary dislocations are consistent with a dissociation reaction in the boundary of the incoming crystal dislocations to produce two ¼⟨111⟩ partial grain boundary dislocations. This provides a good compromise between the overall reduction in elastic strain energy and the increase in step height area in the boundary. As deformation proceeds, the different sets of grain boundary dislocations interact and further dissociate, so that a new network of grain boundary dislocations is produced. Finally, partial dislocations having a ⅛ component along the [001]½ disorientation axis are also observed.