The diffusion of 71Ge in intrinsic or doped material was studied using radiotracer and micro-sectioning techniques. Two temperature regions were identified. Above 1300K, the results were described by:

D (cm2/s) = 2.5 x 103exp[-4.97(eV)/kT]

Below 1250K, the results were described by:

D (cm2/s) = 3.5 x 10-1exp[-3.93(eV)/kT]

It was found that the high-temperature process was enhanced by both B and As doping whereas the low-temperature process was enhanced by As doping and decreased by B doping. The high-temperature process was attributed to diffusion via self-interstitials and the low-temperature process was attributed to diffusion via vacancies.

G.Hettieh, H.Mehrer, K.Maier: Institute of Physics Conference Series, 1979, 46, 500-7

Figure 4

Diffusivity of Ge in Si90Ge10

(Open circles: compressive; filled circles: relaxed; open squares: tensile)