Self-diffusivity in single crystals was studied at 822 to 1163K by using 71Ge radiotracer and sputtering-sectioning. It was found that the results could be described by:

D (cm2/s) = 2.48 x 101 exp[-3.14(eV)/kT]

Self-diffusion at 870 and 894K was also measured in Ga-doped and Sb-doped samples. It was found that the diffusivity was higher in n-type material and lower in p-type material, when compared with intrinsic material. This was explained in terms of a shift in the Fermi level. It was concluded that this supported the assumption that self-diffusion in this material occurred via a vacancy mechanism.

G.Vogel, G.Hettich, H.Mehrer: Journal of Physics C, 1983, 16[30], 6197-204

Figure 25

Diffusivity of Co, Cr and Fe in Ge

(Squares: Co, circles; Fe; triangles, Cr)