Mesoscopic caverns, in the form of faceted voids, were observed to form when Cu passed through pinholes, to the outer surface, during the epitaxial growth of face-centered cubic Co(111) on Cu(111) near to 500C. It was proved that these pinholes were located mainly at boundaries between face-centered cubic twin domains with ABC and ACB stacking.

Mesoscopic Caverns and Nucleation Twins formed in the Growth of Co on Cu G.L.Zhou, C.P.Flynn: Applied Physics Letters, 1998, 72[1], 34-6