  Grain-boundary grooving is a general phenomenon occurring in all
polycrystalline materials at the intersection between the grain-boundary and
the interface or free surface. It has been studied theoretically for some time.
Grain-boundary grooving in the context of faceted interfaces in particular has
attracted some attention. However, these works did not consider the case of
thin films and the consequences on agglomeration of the shape of the interface.
In this Letter, we compare the agglomeration of thin films with rounded and
faceted interfaces. The shape of the grains can dramatically affect the
agglomeration of polycrystalline thin films by grain-boundary grooving.
Anisotropy plays a central role in the stability against agglomeration of
faceted films. Even a small difference between the interface energies of the
facets can destabilize faceted grains or, on the contrary, it can make them
perfectly stable at any thickness. keywords: grain-boundary grooving, dihedral
angle, faceting, energy, silicide, theory, model.
