In Si/Si1–xGex heterostructures, the lattice mismatch induces x-dependent strains in neighbouring layers. The effect of such a biaxial strain on the migration of P dopants in Si was investigated theoretically. The interstitial-based diffusion process of P could be divided into sequences of various migration steps. A clear preference of diffusion along the compressed direction was found. The applied strain was found to lower the activation energies of most of the steps and thus enhance the overall diffusivity.

Anisotropic Effect of Biaxial Strain on Phosphorus Diffusion in Silicon. E.Rauls: Physical Review B, 2006, 74[7], 075204 (9pp)