Electronically enhanced kink motion on 30° partial dislocations in Ge directly observed by plan-view high resolution electron microscopy

In the high resolution electron microscopic (HREM) images of dislocations in Ge obtained with the electron beam incident normal to the slip plane, 30 degrees partial dislocation lines were extracted by image processing, and kinks in them were identified at atomic resolution. Analysis of sequential images taken from the same dislocation lines revealed that (1) geometrical kinks of different signs, 30 degrees (left) and 90 degrees (right) kinks, are both mobile even at room temperature (2) generation of kink pairs occurs, albeit less frequently, in the course of HREM observations. These results are reasonably understood when considering that the migration of kinks, at least one of the two types, and the formation of the smallest double kinks are enhanced by the electronic excitation that is caused by the electron beam used for the HREM observations. (C) 1998 American Institute of Physics.