An in situ low-angle X-ray diffraction technique was used to investigate interdiffusion in various metal/amorphous-Si nm-scale compositionally modulated multi-layers. The interdiffusivities were deduced by monitoring the decay of the first-order modulation peak as a function of annealing time. Activation enthalpies and pre-exponential factors for interdiffusion in the multi-layers were determined (table 11). The relationship between the atomic-size difference and interdiffusion (table 12) was investigated. The results suggested that a collective atomic-jump mechanism governed interdiffusion in the multi-layers; perhaps involving 8 to 15 atoms moving between extended non-equilibrium defects by thermal activation.

Interdiffusion in nanometer-scale multilayers investigated by in situ low-angle X-ray diffraction W.H.Wang, H.Y.Bai, M.Zhang, J.H.Zhao, X.Y.Zhang, W.K.Wang: Physical Review B, 1999, 59[16], 10811-22

Table 11

Parameters for Interdiffusion in Multi-Layers

Table 12

Bulk Interdiffusivities in Multi-Layers as a Function of Radius Difference