Patent US3908194A successfully refreshed from Google Patents.
US3908194A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Integrated magnetoresistive read, inductive write, batch fabricated magnetic head
Assignee: International Business Machines Corp
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Filing: 1974-08-19
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Granted: 1975-09-23
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Expires: 1994-08-19
Abstract
Abstract A thin film head includes a permeable substrate providing a first shield, which may include a more highly permeable layer on its upper surface for shielding, a layer of permeable material thereon providing a second shield and a first write head leg referred to as the shielding-leg layer and a magnetic gap filled with dielectric material between the substrate and the shieldingleg layer. A magnetoresistive stripe including permeable material extends within the dielectric in said gap near the tip end of the head spaced from the substrate and the shielding-leg layer. An inductive single turn or multiturn writing winding is formed upon a layer of dielectric on the other side of the shielding-leg layer. A second leg layer covers the half of the spiral winding towards the tip end of the head and extends through an opening into contact with the shielding-leg layer.
Inventors
- 👤 Lubomyr T Romankiw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:14
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/3967; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49032; Y10T29/4906; Y10T29/49064
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
318 words
A magnetic recording head for reading from and writing onto a magnetic recording medium comprising: a first magnetic shield of permeable material having substantially planar surface and a first tip end, a first, thin film layer of dielectric material in secure contact with said planar surface of said shield, a thin film magnetoresistive stripe form of magnetic writing head structure in secure contact with said first layer of dielectric material aligned longitudinally adjacent to said tip end at the end of said head adapted to face said recording medium, a second thin film layer of dielectric material in secure contact with said first layer of dielectric and said magnetoresistive structure, thin film conductor means connected to terminals of said magnetoresistive stripe, a thin film shielding-leg layer of a magnetically permeable material providing a second shield and a first write leg in secure contact with said second layer of dielectric material extending alongside said magnetoresistive stripe substantially parallel to said planar surface of said first shield having a second tip end adjacent said first tip end to define a magnetic gap, a third thin film layer of dielectric material in secure contact with said second shield, at least one thin film electrical winding in secure contact with said third thin film layer passing near said second tip end, a fourth thin film dielectric layer in secure contact with said winding and said third dielectric layer having a slot therein extending through said winding centrally thereof and through said third dielectric layer to said shielding-leg layer, and a second leg layer having a third tip end aligned with said first and second tip ends and extending through said slot into magnetic contact with said shielding-leg layer whereby said winding extends between said shielding-leg layer and said second leg layer for providing magnetic writing fields across the gap between said tip ends of said shielding-leg layer and said second leg layer.
Claim 2
Dependent Claim
318 words
A magnetic recording head for reading from and writing onto a magnetic recording medium comprising: a first magnetic shield of permeable material having substantially planar surface and a first tip end, a first, thin film layer of dielectric material in secure contact with said planar surface of said shield, a thin film magnetoresistive stripe form of magnetic writing head structure in secure contact with said first layer of dielectric material aligned longitudinally adjacent to said tip end at the end of said head adapted to face said recording medium, a second thin film layer of dielectric material in secure contact with said first layer of dielectric and said magnetoresistive structure, thin film conductor means connected to terminals of said magnetoresistive stripe, a thin film shielding-leg layer of a magnetically permeable material providing a second shield and a first write leg in secure contact with said second layer of dielectric material extending alongside said magnetoresistive stripe substantially parallel to said planar surface of said first shield having a second tip end adjacent said first tip end to define a magnetic gap, a third thin film layer of dielectric material in secure contact with said second shield, at least one thin film electrical winding in secure contact with said third thin film layer passing near said second tip end, a fourth thin film dielectric layer in secure contact with said winding and said third dielectric layer having a slot therein extending through said winding centrally thereof and through said third dielectric layer to said shielding-leg layer, and a second leg layer having a third tip end aligned with said first and second tip ends and extending through said slot into magnetic contact with said shielding-leg layer whereby said winding extends between said shielding-leg layer and said second leg layer for providing magnetic writing fields across the gap between said tip ends of said shielding-leg layer and said second leg layer.
Claim 3
Dependent Claim
31 words
A head in accordance with claim 1 wherein said magnetoresistive stripe is composed of a sandwich of a hard bias material and a magnetoresistive sensor separated by a high resistivity layer.
Claim 4
Dependent Claim
22 words
A head in accordance with claim 1 wherein said first shield comprises a slab of ferrite with a layer of permalloy thereon.
Claim 5
Independent Claim
138 words
A method of fabricating a magnetoresistive read, inductive write head comprising: a. depositing a dielectric layer upon a shielding substrate, b. depositing magnetoresistive material upon said substrate, and forming a magnetoresistive stripe, c. depositing conductors through a mask to contact ends of said stripe, d. applying a second layer of dielectric, e. applying a central layer of permeable material to said second layer of dielectric, f. applying a third layer of dielectric to said central layer, g. applying windings to said third layer through using a mask, h. applying a fourth layer of dielectric, i. exposing openings to each of said conductors, terminals of said windings and to said central layer, and j. depositing a top layer of permeable material through said openings to provide pads and a top leg layer for said head by employing masking techniques.
Claim 6
Independent Claim
138 words
A method of fabricating a magnetoresistive read, inductive write head comprising: a. depositing a dielectric layer upon a shielding substrate, b. depositing magnetoresistive material upon said substrate, and forming a magnetoresistive stripe, c. depositing conductors through a mask to contact ends of said stripe, d. applying a second layer of dielectric, e. applying a central layer of permeable material to said second layer of dielectric, f. applying a third layer of dielectric to said central layer, g. applying windings to said third layer through using a mask, h. applying a fourth layer of dielectric, i. exposing openings to each of said conductors, terminals of said windings and to said central layer, and j. depositing a top layer of permeable material through said openings to provide pads and a top leg layer for said head by employing masking techniques.
Claim 7
Dependent Claim
31 words
A method in accordance with claim 4 wherein said conductors are applied by depositing an adhesion layer by evaporation of a highly oxidizable valve type metal prior to evaporating the conductor.
Claim 8
Dependent Claim
39 words
A method in accordance with claim 5 wherein said adhesion layer comprises titanium or chromium applied from 0* to 80* plus a material selected from the group including permalloy, copper and gold with a thickness from 500A to 1,000A.
Claim 9
Dependent Claim
37 words
A method in accordance with claim 5 wherein said adhesion layer includes a layer of a material selected from transition metals and metal alloys applied at a temperature greater than 100*C in the range of about 200*C.
Claim 10
Dependent Claim
38 words
A method in accordance with claim 4 wherein said windings are applied by depositing an adhesion layer by evaporation of an electrode material upon said substrate and subsequently electroplating said winding upon said adhesion layer through resist masks.
Claim 11
Dependent Claim
20 words
A method in accordance with claim 8 wherein said adhesion layer comprises titanium applied from 0* to 80* plus permalloy.
Claim 12
Independent Claim
170 words
A method of fabricating a magnetoresistive read, inductive write head comprising: a. depositing a dielectric layer upon a magnetically shielding substrate, b. depositing magnetoresistive material upon said substrate, c. depositing conductors through a first mask upon said magnetoresistive material, and removing said first mask, d. applying a second resist mask to said conductors and to said magnetoresistive layer, e. removing the magnetoresistive material not protected by said second resist mask, f. applying a second layer of dielectric, g. applying a central layer of permeable material to said second layer of dielectric, h. applying a third layer of dielectric to said central layer, i. applying windings to said thrid layer through using a mask, j. applying a fourth layer of dielectric, k. exposing openings to each of said conductors and said windings and to said central layer, and l. depositing a top layer of permeable material through said openings to provide pads and a top write head leg layer for the inductive writing segment of said head by employing masking techniques.
Claim 13
Independent Claim
170 words
A method of fabricating a magnetoresistive read, inductive write head comprising: a. depositing a dielectric layer upon a magnetically shielding substrate, b. depositing magnetoresistive material upon said substrate, c. depositing conductors through a first mask upon said magnetoresistive material, and removing said first mask, d. applying a second resist mask to said conductors and to said magnetoresistive layer, e. removing the magnetoresistive material not protected by said second resist mask, f. applying a second layer of dielectric, g. applying a central layer of permeable material to said second layer of dielectric, h. applying a third layer of dielectric to said central layer, i. applying windings to said thrid layer through using a mask, j. applying a fourth layer of dielectric, k. exposing openings to each of said conductors and said windings and to said central layer, and l. depositing a top layer of permeable material through said openings to provide pads and a top write head leg layer for the inductive writing segment of said head by employing masking techniques.
Claim 14
Dependent Claim
34 words
A method in accordance with claim 10 including depositing a passivating layer upon said top layer by sputtering 2 - 5 Mu meters of an inorganic mechanically hard, etchable, wear resistant, easily deposited dielectric.
Claim 15
Dependent Claim
260 words
A magnetic recording head for reading from and writing onto a magnetic recording medium comprising: a first magnetic shield of permeable material having substantially planar surface and a first tip end, a first, thin film layer of dielectric material in secure contact with said planar surface of said shield, a thin film magnetoresistive stripe form of magnetic writing head structure in secure contact with said first layer of dielectric material aligned longitudinally adjacent to said tip end at the end of said head adapted to face said recording medium, a second thin film layer of dielectric material in secure contact with said first layer of dielectric and said magnetoresistive structure, thin film conductor means connected to terminals of said magnetoresistive stripe, a thin film shielding-leg layer of a magnetically permeable material providing a second shield and a first write leg in secure contact with said second layer of dielectric material extending alongside said magnetoresistive stripe substantially parallel to said planar surface of said first shield having a second tip end adjacent said first tip end to define a magnetic gap, at least one thin film electrical winding in secure contact with said shielding-leg layer near said second tip end, a second leg of magnetically permeable material having a third tip end aligned with said first and second tip ends and extending into magnetic contact with said shielding-leg layer whereby said winding extends between said shielding-leg layer and said second leg for providing magnetic writing fields across the gap between said tip ends of said shielding-leg layer and said second leg.
Claim 16
Dependent Claim
260 words
A magnetic recording head for reading from and writing onto a magnetic recording medium comprising: a first magnetic shield of permeable material having substantially planar surface and a first tip end, a first, thin film layer of dielectric material in secure contact with said planar surface of said shield, a thin film magnetoresistive stripe form of magnetic writing head structure in secure contact with said first layer of dielectric material aligned longitudinally adjacent to said tip end at the end of said head adapted to face said recording medium, a second thin film layer of dielectric material in secure contact with said first layer of dielectric and said magnetoresistive structure, thin film conductor means connected to terminals of said magnetoresistive stripe, a thin film shielding-leg layer of a magnetically permeable material providing a second shield and a first write leg in secure contact with said second layer of dielectric material extending alongside said magnetoresistive stripe substantially parallel to said planar surface of said first shield having a second tip end adjacent said first tip end to define a magnetic gap, at least one thin film electrical winding in secure contact with said shielding-leg layer near said second tip end, a second leg of magnetically permeable material having a third tip end aligned with said first and second tip ends and extending into magnetic contact with said shielding-leg layer whereby said winding extends between said shielding-leg layer and said second leg for providing magnetic writing fields across the gap between said tip ends of said shielding-leg layer and said second leg.
Claim 17
Dependent Claim
31 words
A head in accordance with claim 12 wherein said magnetoresistive stripe is composed of a sandwich of a hard bias material and a magnetoresistive sensor separated by a high resistivity layer.
Claim 18
Independent Claim
90 words
A method of fabricating a magnetoresistive read, inductive write heaD comprising: a. depositing a dielectric layer upon a shielding substrate, b. depositing magnetoresistive material upon said substrate, and forming a magnetoresistive stripe, c. depositing conductors through a mask to contact ends of said stripe, d. applying a second layer of dielectric, e. applying a central layer of permeable material to said second layer of dielectric, f. applying a winding to said central layer, g. applying a top layer of permeable material to provide a top leg layer for said head.
Claim 19
Independent Claim
90 words
A method of fabricating a magnetoresistive read, inductive write heaD comprising: a. depositing a dielectric layer upon a shielding substrate, b. depositing magnetoresistive material upon said substrate, and forming a magnetoresistive stripe, c. depositing conductors through a mask to contact ends of said stripe, d. applying a second layer of dielectric, e. applying a central layer of permeable material to said second layer of dielectric, f. applying a winding to said central layer, g. applying a top layer of permeable material to provide a top leg layer for said head.
Claim 20
Dependent Claim
30 words
A method in accordance with claim 14 wherein said conductors are applied by depositing an adhesion layer by evaporation of highly oxidizable valve type metal prior to evaporating the conductor.
Claim 21
Dependent Claim
32 words
A method in accordance with claim 15 wherein said adhesion layer comprises titanium or chromium applied from 0* to 80* plus a permalloy or Cu or Au from 800A to 1,000A thick.
Claim 22
Dependent Claim
37 words
A method in accordance with claim 15 wherein said adhesion layer includes a layer of a material selected from transistion metals and metal alloys applied at a temperature greater than 100*C in the range of about 200*C.
Claim 23
Dependent Claim
38 words
A method in accordance with claim 14 wherein said winding is applied by depositing an adhesion layer by evaporation of an electrode material upon said substrate and subsequently electroplating said winding upon said adhesion layer through resist masks.
Claim 24
Dependent Claim
20 words
A method in accordance with claim 18 wherein said adhesion layer comprises titanium applied from 0* to 80* plus permalloy.
Claim 25
Independent Claim
112 words
A method of fabricating a magnetoresistive read, inductive write head comprising: a. depositing a dielectric layer upon a magnetically shielding substrate, b. depositing magnetoresistive material upon said substrate, c. depositing conductors upon said magnetoresistive material, d. applying a resist mask to said conductors and to said magnetoresistive layer, e. removing the magnetoresistive material not protected by said resist mask, f. applying a second layer of dielectric, g. applying a central layer of permeable material to said second layer of dielectric, h. applying a winding to said central layer, i. depositing a top layer of permeable material to provide a top write head leg layer for the inductive writing segment of said head.
Claim 26
Independent Claim
112 words
A method of fabricating a magnetoresistive read, inductive write head comprising: a. depositing a dielectric layer upon a magnetically shielding substrate, b. depositing magnetoresistive material upon said substrate, c. depositing conductors upon said magnetoresistive material, d. applying a resist mask to said conductors and to said magnetoresistive layer, e. removing the magnetoresistive material not protected by said resist mask, f. applying a second layer of dielectric, g. applying a central layer of permeable material to said second layer of dielectric, h. applying a winding to said central layer, i. depositing a top layer of permeable material to provide a top write head leg layer for the inductive writing segment of said head.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |