Stacking-fault tetrahedron (SFT) is a nano- to micrometer size defect that is generated in epitaxialized films originating from impurity atoms on the substrate. The atomistic process of thermal annihilation of the SFT in Si(111) films was investigated using molecular dynamics simulations. We found that the SFT is annihilated by the movement of Shockley partial dislocations from the top Surface to the SFT bottom apex. (c) 2005 Elsevier B.V. All rights reserved.