The formation of misfit dislocations was investigated in lattice-mismatched InxGa1-xAs epilayers, where x was between 0.2 and 1, which had been grown onto GaAs substrates. The results suggested that 1/3<111> Frank partials were grown-in at island edges in the case of highly lattice-mismatched epilayers (where x was greater than 0.4). After further island growth, 90 Shockley partials then nucleated so as to remove the stacking faults; reacting with the Frank partials in order to form complete 90 dislocations. An atomistic model was proposed in order to explain the formation of the Frank partials. This model was able to explain an observed change, in the predominant dislocation type, from 60 at small mismatches to 90 edge at large lattice mismatches.

Y.Chen, X.W.Lin, Z.Liliental-Weber, J.Washburn, J.F.Klem, J.Y.Tsao: Applied Physics Letters, 1996, 68[1], 111-3