US3967368A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing and using an internally biased magnetoresistive magnetic transducer
Assignee: International Business Machines Corp
•
Filing: 1975-04-30
•
Granted: 1976-07-06
•
Expires: 1995-04-30
Abstract
Abstract A magnetic transducer exhibiting the magnetoresistive (MR) effect is made by depositing at least two thin film layers. An MR film placed in electrical contact with a higher resistivity layer is magnetically biased by a portion of the MR sense current shunted through the nonmagnetic layer.
Inventors
- 👤 George W. Brock
- 👤 Frank B. Shelledy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:59
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/09; B; B82; B82Y; B82Y25/00; G01R33/093; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; H; H01; H01F; H01F1/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49021; Y10T29/49032; Y10T29/49036; Y10T29/49043; Y10T29/49044; Y10T29/49046
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
141 words
A method of manufacturing a magnetic read head including the steps of: depositing a first layer of insulating material on a magnetic supporting substrate; depositing a second layer of relatively conductive constant resistance material in contact with the first layer; depositing a third layer of variable resistance material exhibiting a magnetoresistive effect directly in contact with the second layer; applying a highly conductive metal to selected areas of the layers; applying a mask to portions of the metalized areas; etching the unmasked areas with an etchant to remove portions of the variable resistance material and highly conductive metal; depositing a layer of insulating material over the remaining portions of the variable resistance material and highly conductive metal; and placing a magnetic covering over aforesaid layer wherein said magnetic covering and said magnetic substrate comprise pole pieces in said magnetic read head.
Claim 2
Independent Claim
141 words
A method of manufacturing a magnetic read head including the steps of: depositing a first layer of insulating material on a magnetic supporting substrate; depositing a second layer of relatively conductive constant resistance material in contact with the first layer; depositing a third layer of variable resistance material exhibiting a magnetoresistive effect directly in contact with the second layer; applying a highly conductive metal to selected areas of the layers; applying a mask to portions of the metalized areas; etching the unmasked areas with an etchant to remove portions of the variable resistance material and highly conductive metal; depositing a layer of insulating material over the remaining portions of the variable resistance material and highly conductive metal; and placing a magnetic covering over aforesaid layer wherein said magnetic covering and said magnetic substrate comprise pole pieces in said magnetic read head.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein the second layer is a material belonging to the class of materials including titanium and the third layer is a material belonging to the class of materials including Permalloy.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-06 | 1980-01-05 | 1980-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-06 | 1984-01-05 | 1984-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-06 | 1988-01-05 | 1988-07-06 | $7700.00 | Window Closed / Lapsed |