Misfit Dislocations in Epitaxial Heterostructures: Mechanisms of Generation and Multiplication

In this paper, the regularities of dislocation pattern formation in single layer heterostructures with low lattice mismatch (f < 1%) are reviewed. The main attention is focused on the recently suggested mechanisms of dislocation nucleation and multiplication. An evolution of dislocation pattern from regular flat misfit dislocation network to the dense three-dimensional one was found to proceed during the epitaxial growth. Experimentally found regularities of dislocation structure formation are treated in terms of the influence of the nature of materials contacting at the interface upon the dislocation behavior. Special emphasis is given to the role of microsegregations and selfpoint defects in the alloy matrix in dislocation generation, propagation and multiplication.