Surface morphological evolutions on single crystal films by strong anisotropic drift-diffusion under the capillary and electromigration forces

TL;DR

This paper investigates how anisotropic drift-diffusion influences surface morphology evolution in single crystal metallic films under electromigration and capillary forces, using advanced simulations and a novel mathematical model.

Contribution

It introduces a new mathematical model to simulate surface evolution considering anisotropic drift-diffusion effects under electromigration and capillary forces.

Findings

Interconnect failure time due to wedge-shaped voids is quantified.

Incubation time for oscillatory surface waves is determined.

Surface morphological scenarios depend on texture and electric field direction.

Abstract

The morphological evolution of voids at the unpassivated surfaces and the sidewalls of the single crystal metallic films are investigated via computer simulations by using the novel mathematical model developed by Ogurtani relying on the fundamental postulates of irreversible thermodynamics. The effects of the drift-diffusion anisotropy on the development of the surface morphological scenarios are fully explored under the action of the electromigration (EM) and capillary forces (CF), utilizing numerous combination of the surface textures and the directions of the applied electric field. The interconnect failure time due to the EM induced wedge shape internal voids and the incubation time of the oscillatory surface waves, under the severe instability regimes, are deduced by the novel renormalization procedures applied on the outputs of the computer simulation experiments.