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The origin of high uniaxial magnetic asnisotropy in FeCoB thin films was investigated by focusing on the changes in FeCo crystal distortion and alignment. The films were prepared by facing targets sputtering using [Fe.sub.68.8] [Co.sub.27.2] [B.sub.4] alloy targets and examined with X-ray diffraction (XRD) analysis. Preparation of a Ru underlayer showed reduction of coercivity [H.sub.c] from 130 to 14 Oe and developed remarkably high-anisotropy field [H.sub.k] of 500 Oe. FeCo(110) of the FeCoB film with a Ru underlayer revealed an oblique crystal growth and a preferred orientation in the film plane that possessed (110) [110] along the easy axis. FeCo(110) lattice spacing has 0.5% expansion along the easy axis, which induces that the magnetoelastic energy [E.sub.elastic] of 3.8 x [10.sup.5] erg/[cm.sup.3] exists along the easy axis due to an inverse magnetostriction effect. The estimated [H.sub.k] from the [E.sub.elastic] was 470 Oe, which corresponded well with the measured [H.sub.k] of 500 Oe. This indicates that the strain in FeCo lattice is the origin of the remarkably high magnetic anisotropy. Index Terms--Crystalline texture, FeCoB, high-anisotropy field, Ru, stress-induced magnetic anisotropy.

Playback performances and microstructures of facing targets sputtered (FTS) longitudinal recording tape media on moving tape substrates were investigated at a fast (100 cm/min) and a slow (5.8 cm/min) moving speed. CoPtCr-Si[O.sub.2] granular magnetic layers were deposited on Ru underlayer on moving 4.5 [micro]m thick Aramid films by a FTS system at room temperature. Coercivity over 300 kA/m and grain structures with average diameter of 8 nm were achieved on very thin plastic film. Moving speed does not affect microstructure grown by FTS. The magnetic grains are physically isolated by segregation of silicon and chromium to grain boundaries. This was observed by transmission electron microscopy (TEM) and spot energy-dispersive X-ray spectroscopy (EDS). Cross-sectional TEM images show that straight columnar magnetic grains were grown and unaffected by the moving direction of the substrate. In playback tests, it was shown that both samples had over 8 dB higher SNR than commercial particulate tape media of 0.5 Gb/[in.sup.2] areal density. Index Terms--Facing targets sputtering, magnetic tape recording, playback performance, sputtered tape media.

Bcc-FeCo (110) textured Ru/FeCoB films with high in-plane anisotropy field Hk were prepared as crystalline soft magnetic underlayers (SULs). The differences in crystallographic texture of the Ru intermediate layer (IML) and magnetic properties of Ru/CoPtCr-SiO2 films with or without a FeCoB crystalline SUL were investigated. Ru/CoPtCr-SiO2 films without Ru/FeCoB SULs exhibited a random orientation of Ru crystallites and in-plane magnetic anisotropy. On the other hand, Ru/CoPtCr-SiO2 films deposited on the Ru/FeCoB SULs exhibited (001) preferential orientations of the CoPtCr as well as the Ru IMLs and possessed perpendicular magnetic anisotropy. The reduction of the thickness of the Ru IML from 30 nm to 1 nm did not cause the degradation of integrated intensity of the CoPtCr (002) diffraction peak. The application of the Si/NiFe/FeCoB SUL improved the FeCo (110) crystalline orientation, compared to the Ru/FeCoB SUL, and promoted (001) crystalline orientation of the CoPtCr-SiO2 granular recording layer. The correlative relationship between Δθ50 of FeCo (110) texture and that of CoPtCr (002) texture was confirmed. [ABSTRACT FROM AUTHOR]

Magnetic recording characteristics of a thin-film sputtered media on tape are studied with an HDD head in a high precision nano-positioning system. Signal spectrum roll-off slope is used to determine the effective magnetic spacing to be about 108 nm. The optimum broadband SNR at a linear density of 254 kbpi is 10 dB with a GMR read width of 0.1 μm. The estimated minimum track pitch, limited by side-track interference, is approximately 0.45 μm. [ABSTRACT FROM AUTHOR]

Magnetic recording characteristics of a thin-film sputtered media on tape are studied with an HDD head in a high precision nano-positioning system. Signal spectrum roll-off slope is used to determine the effective magnetic spacing to be about 108 nm. The optimum broadband SNR at a linear density of 254 kbpi is 10 dB with a GMR read width of 0.1 μm. The estimated minimum track pitch, limited by side-track interference, is approximately 0.45 μm. [ABSTRACT FROM AUTHOR]