EP0471946A2
Expired / Lapsed
EP
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High magnetic moment materials and process for fabrication of thin film heads
Assignee: International Business Machines Corp
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Filing: 1991-06-26
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Granted: —
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Expires: 2011-06-26
Abstract
Abstract Certain alloys of CoFeCu are provided in film and laminate form which have a unique combination of electromagnetic properties which enable them to be used as magnetic thin films in magnetic recording heads, shields and flux guides. The films and laminates thereof are electrodeposited from a plating bath in a DC or pulsed current electrodeposition process. <IMAGE>
Inventors
- 👤 Panayotis Constantinou Andricacos
- 👤 Jei-Wei Chang
- 👤 Wilma Jean Horkans
- 👤 Judith Diane Olsen
- 👤 Bojon Petek
- 👤 Lubomyr T. Romankiw
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 23:30
CPC Classifications
H; H01; H01F; H01F41/00; H01F41/14; H01F41/24; H01F41/26; B; B82; B82Y; B82Y25/00; C; C25; C25D; C25D3/00; C25D3/02; C25D3/56; C25D5/00; C25D5/10; C25D5/12; C25D5/18; C25D7/00; C25D7/001; G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; H01F10/00; H01F10/08; H01F10/10; H01F10/12; H01F10/16; H01F10/26; H01F10/30; H01F10/32; H01F10/324; H05; H05K; H05K9/00; H05K9/0073; H05K9/0075; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/11; Y10T428/115; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12778; Y10T428/12861; Y10T428/12903; Y10T428/1291; Y10T428/12917
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
19 words
A laminate comprising a magnetic thin film alloy of Co, Fe and Cu laminated to a non-magnetic thin film.
Claim 2
Dependent Claim
13 words
The laminate of claim 1, wherein said non-magnetic film is Cu or CuCo.
Claim 3
Dependent Claim
124 words
The laminate of claim 1 or 2 wherein the magnetic thin film alloy is an alloy comprising Co x Fe y Cu z wherein x, y, and z represent, respectively, the weight % of Co, Fe and Cu in said alloy and x = about 66 to 92, preferably about 73 to 86 y = about 6 to 14, preferably about 11 to 13 z = about 2 to 20, preferably about 3 to 14, and wherein the weight percent composition therefor shown in the cross-hatched area of Figure 5 of the drawings, wherein the weight percents of said iron and copper are actually disclosed in said cross-hatched area, and the weight percent of said cobalt is obtained by difference, to 100 weight percent.
Claim 4
Dependent Claim
63 words
The laminate of claim 1, 2 or 3 wherein the magnetic thin film alloy is an alloy of Co, Fe and Cu having a magnetic moment value of about 16 000 to 24 000 Gauss, and/or an anisotropy value of about 11 to 20 Oe, and/or a coercivity value of less than 1 Oe, and/or a magnetostriction value of about +10⁻⁴ to -10⁻⁴.
Claim 5
Dependent Claim
27 words
The laminate of anyone of claims 1 to 4 wherein the magnetic thin film alloy is Co₈₆ Fe₁₁ Cu₁₃, or Co₇₉ Fe₁₂ Cu₉, or Co₇₃ Fe₁₃ Cu₁₄.
Claim 6
Dependent Claim
40 words
A magnetic thin film comprising an alloy of cobalt, iron and copper as defined in one or more of claims 1 to 5, or a plurality of said such defined thin films of said alloy of cobalt, iron and copper.
Claim 7
Dependent Claim
28 words
A magnetic thin film as in claim 6, wherein said plurality of thin films of said alloy is separated by non-magnetic thin films, esp. of Cu or CuCo.
Claim 8
Dependent Claim
27 words
A magnetic recording head comprising a laminate of claim 1, or anyone of claims 2 to 5, or a magnetic thin film of claim 6 or 7.
Claim 9
Dependent Claim
26 words
A magnetic shield comprising a laminate of claim 1, or anyone of claims 2 to 5, or a magnetic thin film of claim 6 or 7.
Claim 10
Dependent Claim
20 words
A magnetic recording head in accordance with claim 9 having poletips which are about 0.1 to 5.0 microns in thickness.
Claim 11
Dependent Claim
61 words
Method of electrodepositing a laminated film of alternate layers of at least one magnetic layer and at least one non-magnetic layer comprising: alternately electroplating a magnetic layer comprised of a ternary alloy and a non-magnetic layer comprised of at least one element of said ternary alloy, out of one electroplating bath containing each of the three elements of said ternary alloy.
Claim 12
Dependent Claim
56 words
The method of claim 11 wherein the magnetic and non-magnetic layers are electroplated by alternating pulsing a cathode in said bath at a high plating current and a low plating current, respectively, and/or by alternately pulsing a cathode in said bath at a plating current having a long pulse duration and a short pulse duration, respectively.
Claim 13
Dependent Claim
27 words
The method of claim 12 where said high plating current pulse has a long pulse duration and said low plating current pulse has a short pulse duration.
Claim 14
Dependent Claim
20 words
The method of claim 11, 12 or 13 wherein the three elements in said bath are Co, Fe and Cu.
Claim 15
Dependent Claim
20 words
The method of claim 11, 12 or 13 wherein the three elements in said bath are Ni, Fe and Cu.
Claim 16
Dependent Claim
33 words
The method of claim 12 or 13 and 14 wherein the low plating current is below the Cu diffusion limited current and the high plating current is above the Cu diffusion limited current.
Claim 17
Dependent Claim
33 words
The method of claim 12 or 13 and 15 wherein the low plating current is below the Cu diffusion limited current and the high plating current is above the Cu diffusion limited current.
Claim 18
Dependent Claim
13 words
The method of claim 14 wherein the non-magnetic layer is CoCu or Cu.
References Cited (Backward Citations)
No citation records indexed.
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