Strain Relaxation Phenomena In Ge sub x Si sub (1-x)/Si Strained Structures.

By in-situ relaxation of metastably strained Ge sub x Si sub (1-x)/Si heterostructures in a transmission electron microscope, we are quantitatively able to study dynamic misfit dislocation phenomena. It is found that dislocation nucleation, propagation and interaction phenomena each play a role in determining the overall rate of strain relaxation during heterostructure growth and/or annealing, their relative importance depending upon the layer compositions, thicknesses, growth/annealing temperatures and times, and the number of layers in the structure.