New mechanism for dislocation blocking in strained layer epitaxial growth
Dislocation interactions play a critical role in plasticity and heteroepitaxial strain relaxation. We use real time transmission electron microscopy observations of the interaction between threading and misfit dislocations in SiGe heterostructures to investigate interactions quantitatively. In addition to the expected long-range blocking of threading segments, we observe a new short-range mechanism which is significantly more effective. Simulations show that this reactive blocking occurs when two dislocations with the same Burgers vector reconnect.
Stach
EA
National Center for Electron Microscopy, LBNL, Berkeley, California 94720, USA.
Schwarz
KW
Hull
R
Ross
FM
Tromp
RM