POLARIZATION-DEPENDENT EXAFS STUDIES OF CHEMICAL AND STRUCTURAL ANISOTROPY IN SPUTTER-DEPOSITED CO78CR22 FILMS

Extended x-ray absorption fine structure measurements of a Co78Cr22 film were performed normal and using incident radiation in order to investigate, respectively, the in-plane and out-of-plane local structure and chemistry. The Fourier transformed EXAFS data illustrates the presence of an anisotropy between the in-plane and out-of-plane structures around Co and Cr atoms. Analysis of the local environments around Co for the two sample orientations indicates the presence of clusters, while fitting of the Cr environment indicates preferential ordering parallel td the film plane. These results are consistent with earlier reports' of a high density of stacking faults perpendicular to the growth axis, supporting the interpretation that a platelet-like texturing exists the columnar microstructure. Cr segregation the film plane provides diffusion paths allowing for; transverse compositional inhomogeneities observed in TEM studies.