Faulted dipoles in GaAs

Faulted dipoles in GaAs have been directly imaged by high-resolution transmission electron microscopy. The dislocation dipoles were introduced into the GaAs by deforming a sample in compression along a 〈110〉 axis. Both the Z character of the dipole and the intrinsic nature of the stacking faults could be determined directly from the high-resolution images. Using convergent-beam electron diffraction, it has been shown that it is possible to determine the polarity of the sample and thereby to differentiate between the α and β partial dislocations.