# HRTEM of Screw Dislocations in a Small Angle Grain Boundary

| The HRTEM picture shows sets of {111} lattice planes for a tilt boundary on {111}. There are three sets of screw dislocations, but only one set can be seen.
|  | The left picture is an overview. The small angle grain boundary is inclined (it is essentially contained between the two red lines); to the far left or right just one of the two grain is seen.
|  | Depending on the local thickness of the grains in the area where they overlap, grain one or grain two dominates the picture.
|  | Traces of the two grains are marked in red and blue; the red trace has been shifted to show the twist angle (and the extension of the boundary). |  | The enlargement with a tracing of a {111} plane shows the effect of the screw dislocation.

With frame

7.2.2 Case Studies: Small Angle Grain Boundaries in Silicon I

© H. Föll (Defects - Script)