The diffusion behavior of ion-implanted As in relaxed Si0.8Ge0.2 was investigated (figure 15). The dopant was observed to diffuse faster in SiGe, than in Si, under equilibrium extrinsic conditions. Simulations of the measured profiles suggested that the ratio of the effective diffusivity in Si0.8Ge0.2, as compared with that in Si, was approximately equal to 7. The As diffusivity in SiGe was retarded under transient diffusion conditions, and the magnitude of the diffusion was roughly the same as that in Si.

Comparison of Arsenic and Phosphorus Diffusion Behavior in Silicon–Germanium Alloys. S.Eguchi, J.L.Hoyt, C.W.Leitz, E.A.Fitzgerald: Applied Physics Letters, 2002, 80[10], 1743-5