US5065270A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin film magnetic recording head with a low resistance coil formed by two processes
Assignee: TDK Corp
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Filing: 1990-05-17
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Granted: 1991-11-12
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Expires: 2010-05-17
Abstract
Abstract A thin film magnetic head comprises a substrate, and magnetic films and a conductive coil which are formed on the substrate to constitute a thin film magnetic circuit, wherein the conductive coil has a shape in cross section so that its upper part has a curved convex surface.
Inventors
- 👤 Tsutomu Koyanagi
- 👤 Fujimi Kimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:52
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
174 words
A thin film magnetic head, comprising: a substrate having a flat horizontal surface; an insulating film provided on said surface; a first conductive coil embedded in said insulating film and a second conductive coil embedded in said insulating film above said first conductive coil, each coil including a plurality of windings, the windings of each coil being uniformly spaced apart and the windings of said second conductive coil being offset in the horizontal direction from the windings of said first conductive coil, each said winding having in cross-section a first part and a second part, said first part being generally trapezoidal in shape, said first part being defined in a photolithographic method, said second part being mounted on said first part and coextensive therewith, said second part having a curved convex upper surface formed by plating, said second part of said first coil being spaced from said first part of said second coil and insulated therefrom by said insulating film; and magnetic films, said coils and said films constituting a thin film magnetic circuit.
Claim 2
Dependent Claim
174 words
A thin film magnetic head, comprising: a substrate having a flat horizontal surface; an insulating film provided on said surface; a first conductive coil embedded in said insulating film and a second conductive coil embedded in said insulating film above said first conductive coil, each coil including a plurality of windings, the windings of each coil being uniformly spaced apart and the windings of said second conductive coil being offset in the horizontal direction from the windings of said first conductive coil, each said winding having in cross-section a first part and a second part, said first part being generally trapezoidal in shape, said first part being defined in a photolithographic method, said second part being mounted on said first part and coextensive therewith, said second part having a curved convex upper surface formed by plating, said second part of said first coil being spaced from said first part of said second coil and insulated therefrom by said insulating film; and magnetic films, said coils and said films constituting a thin film magnetic circuit.
References Cited (Backward Citations)
US4684438A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-11 | 1995-05-13 | 1995-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-11 | 1999-05-13 | 1999-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-11 | 2003-05-13 | 2003-11-12 | $7700.00 | Window Closed / Lapsed |