Dislocation microstructures in Si plastically deformed at RT

Abstract

Dislocation microstructures induced by plastic deformation at roomtemperature in Si have been investigated by TEM. Plastic deformation hasbeen obtained by using two types of technique: deformation under aconfining pressure of 5 GPa in an anisotropic multi-anvil apparatus and bysurface scratching. The TEM observations show common features in the twodeformation substructures which are characteristic of high stress-lowtemperature deformation. The deformation microstructures are built withdislocations with a/2⟨110⟩ Burgers vector in (111) planeswhich are undissociated. Such dislocations are mainly aligned along thescrew orientation and ⟨112⟩ orientations at 30° fromthe Burgers vectors as well as along ⟨132⟩ orientations at41° from the Burgers vector. The occurrence of those Peierls valleysconfirms that different dislocation core configurations from those usuallydealt with at higher temperatures have to be taken into account whendislocations are nucleated at very high stresses.