The critical epilayer thickness for the formation of misfit dislocations at the interface between an epilayer and a substrate with a finite thickness was derived. The analysis was based upon the energy approach, in which the self-energy of the dislocation, the interaction energy between the dislocation and free surfaces; and the lattice mismatch energy of the substrate and epilayer were calculated. In order to satisfy the free surface condition, the superposition principle and Fourier transformation were used to analyze the stress field due to an interface dislocation.

Criteria for Formation of Interface Dislocations in a Finite Thickness Epilayer Deposited on a Substrate T.Y.Zhang, S.Lee, L.J.Guido, C.H.Hsueh: Journal of Applied Physics, 1999, 85[11], 7579-86