X-ray absorption spectroscopy study of buried Co layers in the Co/Mo2C multilayer mirrors

X-ray absorption spectroscopy at the Co K edge was applied to investigate the chemical environment of Co atoms inside Co/Mo2C periodic multilayers. The results show a mixing between Co and Mo2C layers prior to any annealing process, whereas following annealing from300 degrees C pure Co layers are observed. X-ray absorption spectroscopy results are in agreement with previous nuclear magnetic resonance spectroscopy results. They indicate that the pure Co content increases upon annealing, while it is absent in the as-deposited samples. The comparison of the results, based on the analysis of the data obtained on the multilayer samples and some reference materials, reveals that the ordering of Co atoms inside the Co layers increases upon annealing. Copyright (C) 2016 John Wiley & Sons, Ltd