Soft X-ray characterization of perpendicular recording media

Abstract

Various spectroscopy, imaging, and scattering techniques exploit core-level resonances accessible in the soft X-ray energies to obtain magnetic information in thin films with elemental specificity. In this paper, we describe the emerging technique of resonant soft X-ray small-angle scattering (SAS) as a probe of magnetic and chemical variations in recording media on the nanometer scale. In particular, we characterize the grain size of a CoB-Pd multilayer media and magnetic and chemical grain sizes in perpendicular CoPtCr media.Index Terms-Cobalt alloys, electromagnetic scattering by magnetic media, perpendicular magnetic recording, small-angle scattering, X-ray scattering.

Resonant soft X-ray and extreme ultraviolet magnetic scattering in nanostructured magnetic materials: Fundamentals and directions

“…2a) that varies along the sample normal [29,30], while in-plane thin film structure is well-studied in symmetric transmission geometry (Fig. 2b) if transmission samples are feasible [22,31,32]. Off-specular reflectance ( Fig.…”

Advances in nanomagnetism via X-ray techniques

“…In recent years emerging resonant small-angle scattering (SAS) techniques have been exploited to probe in-plane structural and magnetic order, over length scales ranging from the X-ray wavelength l, 1-2 nm, up to $300 nm [244][245][246][247] Magnetic and structural heterogeneities can be separated and quantified by tuning both the energy and polarization of the incoming X-ray radiation. For example, these techniques have been used to investigate the role of Cr in advanced magnetic recording medial alloys.…”

Resonant Soft X‐Ray Techniques to Resolve Nanoscale Magnetism

“…This larger spatial frequency range over which signals are inherently Fourier filtered, coupled with a larger dynamic range, gives scattering significantly greater sensitivity to mixed heterogeneity than microscopy. For example, simultaneous sensitivity to magnetic and chemical structure below the zone-plate resolution limit has been obtained in scattering measurements of granular recording media [91,128,129]. The more open geometry of scattering experiments may make them more amenable to utilization in a variety of sample environments.…”