Dislocation transmission through ∑ = 9 symmetrical tilt boundaries in silicon and germanium

Abstract

In situ experiments using synchrotron X-ray topography and high-voltage electron microscopy (HVEM) have been carried out in order to study dislocation transmission through (122), ∑=9 coincidence tilt boundaries in elemental semiconductors. Both techniques proved that this boundary greatly hinders dislocation motion. However, dislocations with the common ½[011] Burgers vector, parallel to the tilt axis, can be transmitted from one crystal to the other. X-ray experiments brought several other types of transmission to light, but these were not confirmed by HVEM observations. This suggests that they were not true transmission reactions but resulted from the activation of pre-existing nearby dislocation sources by internal stresses arising from dislocation pile-ups against the grain boundary, in the opposite crystal.