Results from diffusion studies of different impurities in biaxially strained Si and Si1−xGex for low x-values will be presented. The structures were all molecular-beam epitaxy (MBE) grown on strain-relaxed Si1−xGex layers, and the impurity profiles were introduced during growth. In particular, attention was paid to the effect of biaxial strain (compressive and tensile) upon the diffusion of pure vacancy-assisted diffusers (Sb and, partly, Ge) and pure interstitial-assisted diffusers (B and P). It was found that compressive biaxial strain retards the diffusion of the interstitial-assisted diffusers, whereas tensile biaxial strain enhanced the diffusion of these impurities. The opposite was the case for the vacancy-assisted diffusers.

The Effect of Biaxial Strain on Impurity Diffusion in Si and SiGe. A.Nylandsted Larsen, N.Zangenberg, J.Fage-Pedersen: Materials Science and Engineering B, 2005, 124-125, 241-4