Interdiffusion in microstructurally different Si/Al multilayered structures.

Two types of a-Si/c-Al multilayers were prepared by magnetron sputter deposition under different sputtering conditions. X-ray diffraction (XRD) and transmission electron microscopy (TEM) techniques were used to analyse the microstructures of the as-deposited multilayers. The multilayers showed different degrees of interface roughness. The c-Al sublayers of the multilayers exhibited different levels of macrostress and microstrain and were of different grain size (corresponding to the sublayer thickness). Interdiffusion coefficients were determined by Auger electron spectroscopic (AES) depth profiling. The results indicated that the initial stage of diffusion annealing involved diffusion of Si along grain boundaries in the Al sublayer. The data obtained for the interdiffusion coefficient were insensitive to the present differences in microstructure between the multilayeres investigated. Crystallization of Si took place if appreciable diffusion of Si along the Al grain boundaries had occurred. Copyright © 2006 John Wiley & Sons, Ltd.