Multi-layers were investigated by using an in situ low-angle X-ray diffraction technique. The temperature-dependent interdiffusivities could be described by an Arrhenius relationship (figure 2):
D (m2/s) = 2.02 x 10-20 exp[-0.24(eV)/kT]
giving a diffusivity of 8.22 x 10-24m2/s at 458K. It was concluded that the extremely small values of the pre-exponential factor, and a clear correlation between the pre-exponential factor and the activation energy for interdiffusion suggested that a collective jump mechanism which involved between 8 and 15 atoms governed interdiffusion in the monolayers.
W.H.Wang, H.Y.Bai, W.K.Wang: Journal of Applied Physics, 1999, 86[8], 4262-6
Table 15
Diffusivity of 110mAg along Mutually Perpendicular
Directions in (111) Ag/Cu Interphase Boundaries
Direction | Temperature (K) | D (m2/s) | sD (m3/s) |
[01¯1] | 881 | 2.38 x 10-16 | 2.76 x 10-20 |
[01¯1] | 773 | 7.75 x 10-18 | 4.64 x 10-21 |
[01¯1] | 720 | 1.00 x 10-18 | 1.32 x 10-21 |
[01¯1] | 674 | 1.33 x 10-19 | 3.63 x 10-22 |
[01¯1] | 593 | 1.81 x 10-21 | 4.93 x 10-23 |
[¯211] | 881 | 2.38 x 10-16 | 3.01 x 10-20 |
[¯211] | 773 | 7.75 x 10-18 | 2.17 x 10-21 |
[¯211] | 673 | 1.27 x 10-19 | 1.47 x 10-21 |