Rippling instability on surfaces of stressed crystalline conductors

Abstract

We report a surface morphological stability analysis for stressed, conducting crystalline solids without and with the simultaneous application of an electric field based on self-consistent dynamical simulations according to a fully nonlinear model. The analysis reveals that in addition to a cracklike surface instability, a very-long-wavelength instability may be triggered that leads to the formation of secondary ripples on the surface morphology. We demonstrate that the number of ripples formed scales linearly with the wavelength of the initial perturbation from the planar surface morphology and that a sufficiently strong electric field inhibits both the cracklike and the rippling instability.

The effect of a thermal gradient on the electromigration-driven surface morphological stabilization of an epitaxial thin film on a compliant substrate

“…[13][14][15] Furthermore, the morphological evolution of a thin epitaxial film grown on a deformable substrate has been analyzed. 16 In previous studies, 17,18 we have demonstrated that surface electromigration due to a sufficiently strong and properly applied external electric field can inhibit the ATG instability and prevent surface cracking of stressed elastic conductors. We have also demonstrated that a sufficiently strong and properly directed electric field can inhibit the SK instability in a heteroepitaxial film/substrate system and stabilize the planar surface morphology of a coherently strained epitaxial film.…”