The transport of ion-implanted F in amorphous material was studied by using secondary ion mass spectroscopy and transmission electron microscopy. Significant redistribution of F was observed at 600 to 700C. The F depth profiles were modelled by using a simple Gaussian solution to the diffusion equation, and the diffusion coefficient was deduced for each temperature. It was found that the results (figure 5) could be described by:

D (cm2/s) = 0.1 exp[-2.2(eV)/kT]

The F transport was affected by implantation-induced defects.

Activation Energy for Fluorine Transport in Amorphous Silicon G.R.Nash, J.F.W.Schiz, C.D.Marsh, P.Ashburn, G.R.Booker: Applied Physics Letters, 1999, 75[23], 3671-3

Figure 6

Diffusivity of Fe in Si

(Open circle: present result for Fei+; filled circles: previous results for Fei+; open square: present result for Fei0; filled squares: previous results for Fei0)