The self-diffusion of implanted 71Ge in relaxed Si0.20Ge0.80 layers was studied at 730 to 950C (figure 18) by using a modified radiotracer technique. The temperature dependences of the diffusion coefficients were found to be described by:

D (m2/s) = 8.1 x 10-3 exp[-3.5(eV)/kT]

These results suggested that 71Ge diffused via a vacancy mechanism. Since, in Si0.20Ge0.80, 71Ge diffused only slightly faster than 31Si, the former could be used as a substitute for the inconveniently short-lived 31Si radiotracer in self-diffusion studies of Si-Ge.

Self-Diffusion of 31Si and 71Ge in Relaxed Si0.20Ge0.80 Layers. P.Laitinen, A.Strohm, J.Huikari, A.Nieminen, T.Voss, C.Grodon, I.Riihimäki, M.Kummer, J.Äystö, P.Dendooven, J.Räisänen, W.Frank, Isolde: Physical Review Letters, 2002, 89[8], 085902 (4pp)