The relationships between extended defect evolution and B diffusion in Si0.77Ge0.23 were investigated. A SiGe structure was grown by molecular beam epitaxy with a 3 x 1018/cm3 B marker layer positioned 0.50μm below the surface. Samples were ion implanted with 60keV Si+ at a dose of 1014atoms/cm2 and subsequently annealed at 750C for various times. The evolution of extended defects in the near surface region was monitored with plan-view transmission electron microscopy. Secondary ion mass spectroscopy concentration profiles facilitated the characterization of B diffusion. Boron experiences transient enhanced diffusion regulated by the dissolution of dislocation loops. The maximum diffusion enhancement in Si0.77Ge0.23 was less than that observed in pure Si.

Dislocation Loops in Silicon-Germanium Alloys - the Source of Interstitials. R.T.Crosby, K.S.Jones, M.E.Law, L.Radic, P.E.Thompson, J.Liu: Applied Physics Letters, 2005, 87[19], 192111 (3pp)