Magnetic thin film disks with a nonuniform composition

Chemistry: electrical and wave energy – Processes and products – Coating – forming or etching by sputtering

Reexamination Certificate

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C204S192200, C204S192150

Reexamination Certificate

active

06979388

ABSTRACT:
A method of influencing variations in composition of thin films is described. The elemental plasma field distribution in sputtering systems is manipulated by generating a nonuniform electric field along a surface of the substrate to alter the composition by differentially re-sputtering the target elements. The nonuniform electric field is used to modulate the kinetic energy of the ions generated in the plasma which strike the thin film's surface. By applying varying electric potentials at a plurality of points on a conductive surface of a substrate, the electric field across the surface of the substrate can be modulated in a variety of patterns. In the preferred embodiment a radial voltage gradient is applied to a conductive surface of a disk on which a magnetic thin film is being formed to radially modulate the platinum content of the magnetic film.

REFERENCES:
patent: 4259392 (1981-03-01), Suzuki
patent: 4588653 (1986-05-01), Wray
patent: 4626336 (1986-12-01), Bloomquist et al.
patent: 4663009 (1987-05-01), Bloomquist et al.
patent: 4834855 (1989-05-01), Bloomquist et al.
patent: 5084152 (1992-01-01), Lin
patent: 5304878 (1994-04-01), Oda et al.
patent: 5324593 (1994-06-01), Lal et al.
patent: 5352501 (1994-10-01), Miyamoto et al.
patent: 5356522 (1994-10-01), Lal et al.
patent: 5432012 (1995-07-01), Lal et al.
patent: 5434104 (1995-07-01), Cain et al.
patent: 5492745 (1996-02-01), Yokoyama
patent: 5494722 (1996-02-01), Oka et al.
patent: 5496632 (1996-03-01), Yamaguchi et al.
patent: 5520981 (1996-05-01), Yang et al.
patent: 5523173 (1996-06-01), Doerner et al.
patent: 5626970 (1997-05-01), Hedgcoth
patent: 5650889 (1997-07-01), Yamamoto et al.
patent: 5693197 (1997-12-01), Lal et al.
patent: 5725739 (1998-03-01), Hu
patent: 5750230 (1998-05-01), Ishikawa
patent: 5891311 (1999-04-01), Lewis et al.
patent: 62092847 (1988-10-01), None
Cuomo, Gambino and Rosenberg, “The influence of bias on the deposition of metallic films in rf and dc sputtering”, J. Vac. Sci. Technology, vol. 11, No. 1, Jan./Feb. 1974, XP002218313, pp. 34-40.
A. Moje, European Patent Office, International Search Report for related application PCT/GB 02/03800.
N. Tani, “Increase of Coercive Force in Sputtered Hard Disk”, IEEE Transactions on Magnetics, vol. 26, No. 4, Jul. 1990, pp. 1282ff.
J. Pressesky, et al., “Crystallography and Magnetic Properties of CoCrTa Films Prepared on Cr Underlayers with Different Substrate Bias Conditions”, J. Appl. Physics 69(8). Apr. 15, 1991.
H. Murata, et al., “Magnetic Properties and Microstructure of CoCrTa/Cr Magnetic Recording Media”, Magnetic & Electronic Materials Research Laboratory, Hitachi Metals, Ltd.; vol. 16, No. 3, 1992, pp. 541ff.
S. Parkin, “The magic of magnetic multilayers”; IBM Journal of Research & Development; vol. 42, No. 1, 0018-8646/98, Jan. 26, 1998.
S. Rossnagel, “Sputter deposition for semiconductor manufacturing”; IBM Journal of Research & Development; vol. 43, No. 1, Mar. 20, 1998.
M. Datta, “Applications of electrochemical microfabrication: An Introduction”; IBM Journal of Research & Development; vol. 42, No. 5, 0018-8646/98, Jun. 25, 1998.
D.W. Hoffman, “Intrinsic Re-sputtering—Theory and Experiment”, J. Vac. Sci. Technology, A8(5), 3707, Sep.-Oct. 1990.

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