Stock material or miscellaneous articles – All metal or with adjacent metals – Having composition – density – or hardness gradient
Patent
1992-02-18
1994-06-28
Fuller, Benjamin R.
Stock material or miscellaneous articles
All metal or with adjacent metals
Having composition, density, or hardness gradient
428611, 428668, 428634, 428928, B32B 514, H01F 100
Patent
active
053245938
ABSTRACT:
A magnetic thin-film disc having a magnetic thin film formed of a lower and upper sublayers. The two sublayers are characterized by lower coercivity, smaller grains, and more isolated grains in the lower sublayer, and higher coercivity, and larger grains in the upper sublayer. In one embodiment, the sublayers are characterized by an increasing magnetic remanence on progressing from the outer to the inner diameter of the disc. Also disclosed are sputtering methods for producing the disc.
REFERENCES:
patent: 4259392 (1981-03-01), Suzuki
patent: 4636448 (1987-01-01), Morita et al.
patent: 4798765 (1989-01-01), Ishizaka et al.
patent: 4929514 (1990-05-01), Natarajan et al.
patent: 4988578 (1991-01-01), Yamashita et al.
patent: 5162158 (1992-11-01), Christner et al.
Chen, T., et al., "The Effect of Orientation, Grain Size and Polymorphism on Magnetic Properties of Sputtered Co-Re Thin Film Media," IEEE Trans. Magnetics MAG-17(6):3187-3189 (1981).
Chen, T., and Yamashita, T., "Physical Origin of Limits in the Performance of Thin-Film Longitudinal Recording Media," IEEE Trans. Magnetics 24(6):2700-2705 (1988).
Chen, T., and Charlan, G.B., "High coercivity and high hysteresis loop squareness of sputtered Co-Re thin film," J. Appl. Phys. 50(6):4285-4291 (1979).
Pressesky, J., et al., "Crystallography and magnetic properties of CoCrTa films prepared on Cr underlayers with different substrate bias conditions," J. Appl. Phys. 69(8):5163-5165 (1991).
Sanders, I. L., et al., "Magnetic and Recording Characteristics of Very Thin Metal-Film Media," IEEE Trans. Magnetics 25(5):3869-3871 (1989).
Yamashita, T., et al., "Sputtered Ni.sub.x P Underlayer for CoPt-Based Thin Film Magnetic Media," IEEE Trans. Magnetics 27(6):4727 (1991).
Yogi, T., et al., "Role of atomic mass of underlayer material in the transition noise of longitudinal media," J. Appl. Phys. 69(8):4749 (1991).
Yogi, T., et al., "Longitudinal Media for 1 Gb/in.sup.2 Areal Density," IEEE Trans. Magnetics 26(5):2271-2276 (1990).
Zhu, J.-G., and Bertram, H. N., "Micromagnetic studies of thin metallic films (invited)," J. Appl. Phys. 63(8):3248-3253 (1988).
Eltoukhy Atef H.
Lal Brij B.
Dehlinger Peter J.
Fuller Benjamin R.
HMT Technology Corporation
Lund Valerie Ann
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