Dislocation dynamics and slip band formation in silicon: In-situ study by X-ray diffraction imaging

White beam X-ray diffraction imaging (topography) with an optimised CCD-detector system is used to monitor in-situ and in real time the nucleation, growth and movement of dislocations in silicon at high temperatures. It can be shown, that damage like microcracks and the surrounding strain fields in a wafer act as sources for dislocation loops, which end in slip bands far away from the source. The dislocations are arranged in channels of parallel {111} glide planes, which become visible as bands of parallel surface steps when the dislocations slip out on the back or front sides of the wafer. The width of such a channel or band depend on the dimensions of the damaged volume where the dislocations nucleate. This can be explained with a simple geometrical model.