Extrinsic Dissociation of a Dislocation in GaAs in the Presence of Point Defects

The dissociation of a screw dislocation segment into three partial dislocations in GaAs is reported. The observation is explained by the formation and dissociation of a vacancy or an interstitial 60° diple at the core of one of the 30° partial dislocations of the dissociated screw dislocation. This leads then to the extrinsic dissociation of the extended dislocation. An alternative explanation that involves a Frank dislocation dipole rather than the 60° dipole is also examined. Copyright © 1989 WILEY‐VCH Verlag GmbH & Co. KGaA