COMPUTER-SIMULATION OF STRAIN-INDUCED DIFFUSION ENHANCEMENT OF SI ADATOMS ON THE SI(001) SURFACE

A computer simulation study of the effect of strain on the diffusion of single Si adatoms on a Si(001)(2 x 1) surface has been performed. The Stillinger-Weber potential was used to simulate the interatomic interactions of the atoms. Five layers of atoms were included in the simulation with the three top layers of the Si surface free to reconstruct, leading to surface dimers, and the remaining two layers fixed in the bulk positions. The potential energy map and energy barriers were examined at 0%, 1% and 1.5% strain with the strain applied perpendicular to the dimer rows. The results indicate that diffusion enhancement along the dimer rows may be achieved by strain.