The migration of ion-implanted Au in a monocrystal was studied by using the spreading resistance method. One-dimensional and 2-dimensional diffusion across the wafer and along the wafer were studied by using limited or unlimited Au sources. The data (table 10) could be described by:

D(cm2/s) = 0.28 exp[-1.6(eV)/kT]

It was shown that, by ion-implanting Au, it was possible to produce unique concentration profiles via close control of the number of Au atoms in the diffusion source. This permitted both depth and surface profiles to be tailored. All of the measured profiles were consistent with a kick-out mechanism for Au diffusion.

S.Coffa, L.Calcagno, S.U.Campisano, G.Ferla: Journal of Applied Physics, 1991, 69[3], 1350-4

Table 10

Diffusivity of Au in Si