Abstract
The origin of high uniaxial magnetic anisotropy in FeCoB thin films were studied from the changes in FeCo crystal distortion and alignment. The films were prepared by facing targets sputtering and examined by X-ray diffraction (XRD) analysis. Preparation of Ru underlayer showed remarkably high anisotropy field H_k of 500 Oe. The Ru/FeCoB films revealed an oblique crystal growth and a preferential orientation. FeCo(110) lattice spacing had 0.5 % expansion along the easy axis and the strain indicated magnetoelastic energy E_<elastic> of 3.8×10^5 erg/cc exists along the easy axis. The estimated H_k from the Eelastic was 470 Oe which well corresponded with the measured H_k of 500 Oe. This indicates that the strain in FeCo lattice is the origin of the remarkably high magnetic anisotropy.
