Grain boundaries effects on hole morphology and growth during solid state dewetting of thin films

We probe the effects of grain boundaries on thin film dewetting numerically for initially circular and elongated holes in single and bi-crystalline systems. We find that grain boundaries play a critical role in determining hole morphologies, in particular in the formation of highly branched hole morphologies, since while elongated holes in single crystals tend to become rounder over time, circular holes in bi-crystals destabilize, leading to accelerated dewetting along the grain boundaries.