X-ray reflection anomalous fine structure analysis of the stability of permalloy/copper multilayers

We report the application of reflection anomalous fine structure analysis t o the study of the changes in the layer density and local environment in sp uttered permalloy/copper multilayers. By fitting the smoothly varying compo nent of the plot of multilayer Bragg peak intensity versus incident X-ray e nergy, we find a strained permalloy layer at the permalloy/copper but not t he copper/permalloy interface. The density difference between copper and st rained permalloy layers increases on annealing at 275 degreesC and from the oscillatory component of the spectrum, we show that it is the nearest-neig hbour distance around the Ni atoms which decreases. (C) 2001 Elsevier Scien ce B.V. All rights reserved.