Title :
Local anisotropic structure in amorphous Ba-Fe-O films and its role in determining magnetic anisotropy in crystallized Ba-hexaferrite films
Author :
Snyder, J.E. ; Harris, V.G. ; Koon, N.C. ; Sui, X. ; Kryder, M.H.
Author_Institution :
US Naval Res. Lab., Washington, DC, USA
fDate :
11/1/1995 12:00:00 AM
Abstract :
Ba hexaferrite films with the easy direction of magnetization perpendicular or in-plane can be prepared by crystallization of amorphous films deposited under different sputtering conditions. Using polarization-dependent EXAFS (extended X-ray absorption fine structure), we have observed anisotropic local structure around the Fe atoms in as-sputtered amorphous Ba-Fe-O films. Such structure has not been detectable by conventional structural characterization techniques (X-ray diffraction, electron diffraction and transmission electron microscopy [TEM]). The results suggest that this local structural anisotropy determines the orientation of the fast-growing basal plane directions during post-deposition annealing and thus the directions of the c-axes and the magnetic anisotropy
Keywords :
EXAFS; amorphous magnetic materials; annealing; barium compounds; crystallisation; ferrites; magnetic anisotropy; magnetic thin films; noncrystalline structure; perpendicular magnetic anisotropy; sputtered coatings; BaFe12O19; amorphous Ba-Fe-O films; amorphous films; as-sputtered amorphous Ba-Fe-O films; c-axes; crystallization; crystallized Ba-hexaferrite films; easy magnetisation direction; extended X-ray absorption fine structure; fast-growing basal plane directions; local anisotropic structure; local structural anisotropy; magnetic anisotropy; polarization-dependent EXAFS; post-deposition annealing; sputtering conditions; Amorphous materials; Anisotropic magnetoresistance; Crystallization; Electromagnetic wave absorption; Electrons; Iron; Magnetization; Polarization; Sputtering; X-ray diffraction;
Journal_Title :
Magnetics, IEEE Transactions on
