The initial interdiffusion processes in multi-layer structures were studied quantitatively by means of Auger electron spectroscopic sputter depth-profiling. The Al sub-layers and the Si sub-layers were sputter-deposited onto a Si(111) substrate. The initial stage of interdiffusion at the location of the Si/Al interfaces was induced by heating the specimens isothermally in an Ar atmosphere at 150, 165 and 180C for 1200s, and then at 165C for 600 and 1800s. It was found that, in such sputter-prepared multi-layer structures, interdiffusion across interfaces near to the surface of the multi-layer was faster than across interfaces in the deeper part of the layer. The measured depth profiles of the annealed specimens were compared with that of the as-deposited specimen after quantitative evaluation according to the so-called mixing-roughness information depth model. As a result, values of the interdiffusion coefficient as a function of the depth beneath the surface were obtained.

Determination of the Interdiffusion Coefficient for Si/Al Multilayers by Auger Electron Spectroscopic Sputter Depth Profiling. J.Y.Wang, A.Zalar, Y.H.Zhao, E.J.Mittemeijer: Thin Solid Films, 2003, 433[1-2], 92-6