Single and compositionally graded partially relaxed heterostructures of equivalent lattice mismatch and thickness were characterized by means of high-resolution X-ray diffraction and X-ray double-crystal topography. The latter revealed a rapid decrease in the average length of misfit dislocation segments with increasing density of misfit dislocations. Compositionally-graded heterostructures exhibited much longer misfit dislocation segments than did equivalent single heterostructures; thus confirming the effectiveness of compositional grading in reducing dislocation interaction.

Misfit Dislocation and Threading Dislocation Distributions in InGaAs and GeSi/Si Partially Relaxed Heterostructures. C.Ferrari, G.Rossetto, E.A.Fitzgerald: Materials Science and Engineering B, 2002, 91-92, 437-40