Antiphase boundaries which formed between islands on the (001) surface during epitaxial growth were known to be nucleation sites for new layers of Si and therefore played a key role during growth. Various possible structures for the antiphase boundaries were modelled in order to determine stable structures and the kink energy of the 2 lowest-energy structures. The stability of dimer strings on an antiphase boundary, relative to the same strings on a clean surface, was also demonstrated. This explained why islands were found to nucleate on an antiphase boundary, but did not do so on the clean surface during growth.

Nucleation on antiphase boundaries on Si(001) D.R.Bowler, C.M.Goringe: Physical Review B, 1998, 58[7], 3937-40