Transition metals in amorphous samples exhibit a direct interstitial diffusion behavior which is retarded by temporary trapping at defects that are intrinsic to the amorphous structure. Diffusion was investigated here by means of Rutherford back-scattering spectrometry. It was found that the data (table 201) could be fitted by using foreign-atom interstitial diffusion coefficients for crystalline Si; modified by the presence of traps in concentrations of between 0.2 and 1at%, and with trapping enthalpies of about 0.9eV.

S.Coffa, J.M.Poate, D.C.Jacobson, W.Frank, W.Gustin: Physical Review B, 1992, 45[15], 8355-8

 

Table 201

Diffusivity of Pt in Amorphous Si

 

T (C)

D (cm2/s)

600

2.4 x 10-13

560

4.2 x 10-14

502

5.2 x 10-15

455

3.5 x 10-16