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 94) 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.
Determination of Diffusion Mechanisms in Amorphous Silicon. S.Coffa, J.M.Poate, D.C.Jacobson, W.Frank, W.Gustin: Physical Review B, 1992, 45[15], 8355-8
Table 93
Diffusivity of Pt in Si
Temperature (C) | D (cm2/s) |
1120 | 5.6 x 10-7 |
1085 | 6.0 x 10-7 |
1050 | 4.4 x 10-7 |
1000 | 1.7 x 10-7 |
950 | 8.1 x 10-8 |
Table 94
Diffusivity of Pt in Amorphous Si
Temperature (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 |