It was recalled that Zn in GaAs exhibited a complicated diffusion behavior, as well as a high solid-solubility. The diffusion of Zn, at temperatures of between 700 and 1100C, was studied here by using 3 different Zn diffusion sources. In order to compare the penetration curves for the various sources, reduced penetration depths and reduced concentrations were calculated. Numerical simulation of Zn transport furnished a good description for particular sources. Effective diffusivities (table 26) were deduced from the experimental data and were normalized to standard vapour pressures and electronically intrinsic conditions. The data for normalized Zn diffusion could be described by:

D (cm2/s) = 82.3 exp[-4.03(eV)/kT]

H.G.Hettwer, N.A.Stolwijk, H.Mehrer: Defect and Diffusion Forum, 1997, 143-147, 1117-24

Table 27

Bulk Diffusivity of Zn in GaAs