The faceting of grain boundaries under annealing in phosphorus-doped polysilicon films, produced by low-pressure chemical vapour deposition, was investigated by transmission electron microscopy. It was shown that the facet types and facet density depend on annealing temperature. It was found that grain boundary facets were generally parallel with close-packed planes in coincidence site lattice. A correlation between grain boundary faceting and grain-growth mechanisms was considered. It was shown that faceting takes place both under normal and abnormal grain growth. It was revealed that twinning played  the key role for grain boundary faceting under normal grain growth.

Faceting of Twin Grain Boundaries in Polysilicon Films. N.Nakhodkin, N.Kulish, T.Rodionova: Physica Status Solidi A, 2010, 207[2], 316-20