Microstructures of FeTaN films in the neck region of magnetic recording heads

Abstract

We found that the columns at the neck region of a magnetic recording inductive head slider composed of FeTaN and NiFe are tilted from the surface normal when the pole materials are sputtered at a low substrate bias power. The electron diffraction patterns show that (110) texture has not strongly developed in the FeTaN film. We have not observed noticeable voids throughout the film on the slider, which suggests the absence of microshape anisotropy. This observation is consistent with our previous study of FeTaN blanket films. We confirmed lattice distortion in the FeTaN due to Ta and N incorporation into a Fe matrix. No significant difference in microstructure between the film on the head slider and the blanket film is found. Based on all the information we have gathered, such as X-ray spectra, pole figures, and high-resolution electron micrographs, we established the crystallographic relationship between (110) orientation, columnar direction, and incident atomic flux in the case of oblique-incident deposition of FeTaN films.Index Terms-Fe-based nitride magnetic materials, head sliders, high-saturation-moment magnetic materials, inductive recording heads, oblique-incident deposition.

Soft Magnetic Properties of Obliquely Deposited Co–Zr–O Films

“…The effect of low substrate bias on Co-Zr-O films sputtered on small-angle substrates can be understood on the basis that low substrate bias effectively helps overcome a slight shadowing effect. The worsening of soft magnetic properties with highpower substrate bias in Co-Zr-O films is not usually seen in other soft magnetic films [12]- [14]. We found that high substrate bias leads to larger size and stronger hcp (002) texture of cobalt particles, and even more severe columnar structure.…”

“…Substrate bias has been reported to play a different role in FeTaN films. Changing film stress and the orientation of Fe grains contributed to suppression of the perpendicular anisotropy existing in FeTaN films on sloping surfaces [13], [14].…”

“…Applying substrate bias during film deposition has become established as an effective method to eliminate or compensate for the influence of oblique deposition in Permalloy films [12] and Fe-based soft magnetic films like FeTaN [13], [14]. In Permalloy, the substrate bias was believed to realign and densify the NiFe columns, and thus overcome the shadowing effect [12].…”