Determination of short-range order and interlayer extension in Fe/Al multilayers using XAFS

Shea-range order in Fe/Al multilayers has been determined using Fe K fluore scence x-ray absorption fine structure (XAFS) experiments. The two multilay ers studied (prepared by pulsed laser deposition) exhibited different Fe si ngle layer thickness (4.3 nm and 30 nm, respectively) but comparable total amount of Fe (six thin and one thick layers, respectively). From XAFS signa ls arising at different regions of the sample it was concluded that a solid solution of alpha-Fe had been formed in the vicinity of the Fe/Al interfac e, the thickness of which was estimated to be 3.8 nm. The average Fe neighb ourhood in these interface regions contained about 50% Al substituting for Fe.