Critical thickness for misfit twinning in an epilayer

Abstract

A Somigliana dislocation dipole model is developed to determine the critical thickness for misfit twin formation in an epilayer with different elastic constants from its substrate. The critical dipole arm length is determined by minimizing the twin formation energy for a given epilayer thickness and lattice mismatch strain, while a zero value of the minimum formation energy determines the critical thickness for misfit twinning. The results obtained by the Somigliana dislocation dipole model are roughly consistent with those by the previous dislocation-based twinning model.

DO22–(Cu,Ni)3Sn intermetallic compound nanolayer formed in Cu/Sn-nanolayer/Ni structures

“…A large lattice mismatch makes the critical thickness for misfit dislocation generation [14,15] and misfit twin generation [16,17] small. It will be energetically unstable if the DO 22 -(Cu,Ni) 3 Sn IMC layer is too thick.…”