Regular domain boundaries on the (111)-(7 x 7) surface were investigated theoretically and experimentally. It was found that, in most cases, the defects in the regular domain boundaries were accompanied by dimer-adatom stacking-fault sub-units, from 3 x 3 to 13 x 13, which spanned the regular domain boundaries as matching bridges and stabilizers. Regular domain boundaries with dimer-adatom stacking-fault cores directly revealed dynamic signs of dimer-adatom stacking-fault reconstruction. The total energies of the larger dimer-adatom stacking-fault systems, and interactions between local configurations such as dimers and adatoms, were calculated by using an empirical building-block method which included charge-transfer effects and the dimer-adatom interactions. This study indicated that the larger dimer-adatom stacking-fault system members had lower energies than expected.

Local dimer-adatom stacking-fault structures from 3 x 3 to 13 x 13 along Si(111)-7 x 7 domain boundaries Y.F.Zhao, H.Q.Yang, J.N.Gao, Z.Q.Xue, S.J.Pang: Physical Review B, 1998, 58[20], 13824-9