Title :
Magnetic Anisotropy of FeCo Films Induced by Obliquely Sputtered Ru Underlayers
Author :
Lu, Z. ; Fukuma, Y. ; Butler, W.H. ; Fujiwara, H. ; Mankey, G.J. ; Matsunuma, S.
Author_Institution :
MINT Center, Univ. of Alabama, Tuscaloosa, AL, USA
Abstract :
The magnetic properties of Si/Ru(t nm)/Fe90Co10 (3.0 nm)/Ru (4.0 nm) films with obliquely sputtered Ru underlayers were studied as a function of Ru underlayer thickness (t). It was found that an obliquely sputtered Ru underlayer produces high uniaxial anisotropy in the Fe90Co10 layer with extremely small hysteresis in the hard axis direction. The anisotropy field can be increased by increasing Ru underlayer thickness. X-ray reflectometry showed that the interfaces of the samples were quite smooth with rms roughness as small as 0.35 nm. The high uniaxial anisotropy of the samples shows high thermal stability and endures e-beam lithography for microscopic device fabrication. We discuss the origin of this high anisotropy in terms of a magnetostatic effect arising from an anisotropic surface morphology.
Keywords :
cobalt alloys; electron beam lithography; interface magnetism; iron alloys; magnetic anisotropy; magnetic hysteresis; magnetic thin films; magnetostatics; ruthenium; silicon; sputtered coatings; surface morphology; thermal stability; Si-Ru-Fe90Co10-Ru; X-ray reflectometry; e-beam lithography; hard axis direction; magnetic anisotropy; magnetic films; magnetic hysteresis; magnetic properties; magnetostatic effect; microscopic device fabrication; rms roughness; sputtered Ru underlayers; surface morphology; thermal stability; Multilayered media; thin films;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2009.2024161
