Patent US5384680A successfully refreshed from Google Patents.
US5384680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perpendicular anisotropy in thin film devices
Assignee: PHC Corp
•
Filing: 1993-02-16
•
Granted: 1995-01-24
•
Expires: 2013-02-16
Abstract
Abstract One aspect of the present invention relates to enabling rotational flux conduction through magnetic film devices by creating a magnetic film layer with anisotropy perpendicular to the plane of the film layer, the film deposited in sufficient thickness so that there is a rest state rotational conduction path in the plane of the film layer. Another aspect of the invention is to provide for flux spreading in a magnetic device having perpendicular anisotropy. One feature of the present invention enables forming perpendicularly oriented central domains in a magnetic device so that the path for conduction of signal flux by rotation remains open even for very narrow signal flux paths. Another feature of the invention is to orient at rest domain states of a magnetic device pole (or poles) perpendicular to two desired in-plane rotational flux travel directions. Another feature of the invention is to orient edge domains in this type of magnetic device into a plane where their relative widths do not impact substantially on rotational flux flow through the device for narrow track heads. A preferred embodiment of the present invention includes at least one pole of a magnetic device, formed on a substrate, having a preferred at rest pole domain orientation perpendicular to the substrate plane.
Inventors
- 👤 Michael Mallary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:30
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/31; G11B5/3109; G11B5/3113; G11B5/3116; G11B5/33; G11B5/332; H; H01; H01F; H01F41/00; H01F41/14; Y; Y10; Y10T; Y10T428/00; Y10T428/11; Y10T428/1171; Y10T428/1186
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
204 words
A method for conducting signal flux by rotation in a magnetic structure that is generally disposed in a plane, comprising the steps of providing the magnetic structure with a relatively narrow end region extending along a longitudinal axis in the plane of the structure to a relatively wider base region, providing said end region and said base region of said structure with a magnetic rest state orientation, arranging said magnetic rest state orientation in said end region and said base region transverse to said plane to provide a plurality of paths each of which is generally disposed in said plane for conducting said signal flux by rotation of said magnetic rest state orientation, and applying said signal flux to said end region transversely to said magnetic rest state orientation to cause said end region to conduct said flux by rotation in a first one of said paths along said longitudinal axis to said base region and to cause said base region to conduct said flux by rotation in at least a second one of said paths that is disposed transversely to said longitudinal axis, so that said signal flux spreads away from said longitudinal axis as said signal flux conducts in said base region.
Claim 2
Independent Claim
204 words
A method for conducting signal flux by rotation in a magnetic structure that is generally disposed in a plane, comprising the steps of providing the magnetic structure with a relatively narrow end region extending along a longitudinal axis in the plane of the structure to a relatively wider base region, providing said end region and said base region of said structure with a magnetic rest state orientation, arranging said magnetic rest state orientation in said end region and said base region transverse to said plane to provide a plurality of paths each of which is generally disposed in said plane for conducting said signal flux by rotation of said magnetic rest state orientation, and applying said signal flux to said end region transversely to said magnetic rest state orientation to cause said end region to conduct said flux by rotation in a first one of said paths along said longitudinal axis to said base region and to cause said base region to conduct said flux by rotation in at least a second one of said paths that is disposed transversely to said longitudinal axis, so that said signal flux spreads away from said longitudinal axis as said signal flux conducts in said base region.
Claim 3
Dependent Claim
58 words
The method of claim 1 wherein said structure includes at least one other path for conducting flux other than by rotation, and further comprising providing said structure with a thickness selected to cause said signal flux to follow said at least one of said plurality of paths for conducting signal flux by rotation preferentially to said other path.
Claim 4
Dependent Claim
95 words
The method of claim 2 wherein said step of arranging said rest state orientation causes a first plurality of magnetic domains to be formed in a central region of said structure and a second plurality of magnetic domains to be formed in said structure, said first magnetic domains being orientated perpendicularly to upper and lower surfaces of said structure to provide said path for conducting signal flux by rotation, and further comprising the step of locating said second domains adjacent to said upper and lower surfaces and orienting said second domains parallel to said surfaces.
Claim 5
Dependent Claim
12 words
The method of claim 2, wherein said structure is an iron alloy.
Claim 6
Dependent Claim
12 words
The method of claim 2, wherein said structure is a nickel alloy.
Claim 7
Dependent Claim
12 words
The method of claim 2, wherein said structure is a cobalt alloy.
Claim 8
Dependent Claim
12 words
The method of claim 2, wherein said structure is a magnetic garnet.
Claim 9
Dependent Claim
12 words
The method of claim 2, wherein said structure is a magnetic ferrite.
Claim 10
Dependent Claim
13 words
The method of claim 2, wherein said structure is a soft magnetic film.
Claim 11
Dependent Claim
36 words
The method of claim 1 wherein said step of arranging said rest state orientation comprises forming a plurality of magnetic domains oriented perpendicularly to said plane to provide said paths for conducting signal flux by rotation.
Claim 12
Dependent Claim
40 words
The method of claim 10 further comprising forming a second plurality of magnetic domains formed in said structure, locating said second domains adjacent to upper and lower surfaces of the structure, and orienting said second domains parallel to said surfaces.
Claim 13
Dependent Claim
74 words
The method of claim 10 wherein said step of arranging causes a second plurality of magnetic domains oriented along one of said plurality of paths to be formed, said second domains defining a path for conducting flux other than by rotation, and further comprising providing said structure with a thickness selected to cause said signal flux to conduct along said magnetic domains oriented perpendicularly to said plane preferentially to conducting along said second domains.
Claim 14
Dependent Claim
27 words
The method of claim 12 wherein said thickness is selected to cause said magnetic domains oriented perpendicularly to said plane to be larger than said second domains.
Claim 15
Dependent Claim
19 words
The method of claim 1 further comprising arranging said rest state orientation to be substantially perpendicular to said structure.
Claim 16
Dependent Claim
24 words
The method of claim 1 further comprising arranging said magnetic at rest orientation so that said second path is perpendicular to said first path.
Claim 17
Dependent Claim
19 words
The method of claim 15 further comprising arranging said rest state orientation to be substantially perpendicular to said structure.
Claim 18
Dependent Claim
23 words
The method of claim 1 further comprising forming said structure as a thin-film layer configured to provide a pole for a magnetic head.
Claim 19
Dependent Claim
22 words
The method of claim 17 further comprising providing a transducer coupled to said layer for generating said signal flux in said layer.
Claim 20
Dependent Claim
23 words
The method of claim 17 further comprising providing a transducer coupled to said layer for detecting said signal flux conducting in said layer.
Claim 21
Dependent Claim
29 words
The method of claim 1 further comprising providing a second said layer and coupling said second layer to the first mentioned layer to provide a multiple pole magnetic head.
Claim 22
Dependent Claim
24 words
The method of claim 20 further comprising providing a transducer coupled to at least one of said layers for generating said signal flux therein.
Claim 23
Dependent Claim
25 words
The method of claim 20 further comprising providing a transducer coupled to at least one of said layers for detecting said signal flux conducting therein.
Claim 24
Dependent Claim
90 words
The method of claim 1 further comprising configuring said structure as a pole of magnetic head with said end region forming a tip of said pole having a selected width and said base region forming a yoke of said pole. said step of arranging said rest state orientation comprising forming a plurality of magnetic domains oriented perpendicularly to said plane to provide said paths for conducting signal flux by rotation, and arranging said structure so that one of said magnetic domains is disposed over said selected width of said tip.
Claim 25
Dependent Claim
74 words
The method of claim 23 wherein said step of arranging causes a second plurality of magnetic domains oriented along said first one of said paths to be formed, said second domains defining a path for conducting flux other than by rotation, and further comprising providing said structure with a thickness selected to cause said signal flux to conduct along said magnetic domains oriented perpendicularly to said plane preferentially to conducting along said second domains.
Claim 26
Dependent Claim
101 words
The method of claim 1 wherein said step of arranging said rest state orientation comprises forming a plurality of magnetic domains oriented perpendicularly to said plane to provide said paths for conducting signal flux by rotation and causes a second plurality of magnetic domains oriented along at least one of said paths to be formed, said second domains defining a path for conducting flux other than by rotation, and further comprising providing said structure with a thickness selected to cause said signal flux to conduct along said magnetic domains oriented perpendicularly to said plane preferentially to conducting along said second domains.
Claim 27
Dependent Claim
27 words
The method of claim 25 wherein said thickness is selected to cause said magnetic domains oriented perpendicularly to said plane to be larger than said second domains.
References Cited (Backward Citations)
US3880602A
Cited
US3961299A
Cited
US3967368A
Cited
US3947889A
Cited
US4179719A
Cited
US4103315A
Cited
US4228473A
Cited
US4242710A
Cited
US4374403A
Cited
US4413296A
Cited
US4295173A
Cited
JPS56163517A
Cited
US4356523A
Cited
JPS57141013A
Cited
JPS57164416A
Cited
US4604670A
Cited
US4613918A
Cited
US4564877A
Cited
US4719148A
Cited
JPS59121611A
Cited
US4566050A
Cited
US4535375A
Cited
US4639811A
Cited
EP0154005A2
Cited
US4626946A
Cited
US4745506A
Cited
US4656546A
Cited
US4750072A
Cited
US4668913A
Cited
JPS61229209A
Cited
US4663685A
Cited
US4649447A
Cited
US4698711A
Cited
US4695351A
Cited
US4803580A
Cited
US4891725A
Cited
US4825318A
Cited
US4816947A
Cited
US4912584A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-01-23 | 1998-07-25 | 1999-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-23 | 2002-07-25 | 2003-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-23 | 2006-07-25 | 2007-01-24 | $7700.00 | Window Closed / Lapsed |