The elastic field of an edge dislocation in a half-space with the effect of surface energy was obtained here. The elastic field was then used to study the image force on the dislocation, the critical thickness for dislocation generation in epitaxial thin films with strain mismatch and the yielding strength of thin films on substrates. The results show that the image forces on the dislocation deviate from the conventional solutions when the distance of the dislocation from the free surface was smaller than several times of the characteristic length. Also due to the effect of surface energy, the critical thickness for dislocation generation was smaller than that predicted by the conventional elastic solutions and the extent of the deviation depends on the magnitude of mismatch strain. In contrast, the effect of surface energy on the yielding strength for many practical thin films could be neglected except for some soft ones where the characteristic length was comparable to the thickness.

Effect of Surface Energy on Dislocation-Induced Field in Half-Space with Application to Thin Film-Substrate Systems. G.Huang, B.Svendsen, Z.Lu: Acta Mechanica Solida Sinica, 2009, 22[5], 436-42