Steven J Lambert

US Patent:

6697203, Feb 24, 2004

Filed:

May 24, 2000

Appl. No.:

09/578262

Inventors:

Nelson Cheng - Fremont CA
Bill Higgins - Palo Alto CA
Hai Nguy - San Jose CA
Steven Stupp - Mountain View CA
Steven Lambert - San Jose CA

Assignee:

Maxtor Corporation - Milpitas CA

International Classification:

G11B 2736

US Classification:

360 31, 360 53

Abstract:

A method and apparatus for determining a lifetime for a medium to fail due to thermal decay of a magnetization pattern is provided. Different stress magnetic fields are applied to a write head for writing to a machine-readable medium resulting in a magnetic field on the medium. A time to failure, corresponding to each of the different stress magnetic fields, is determined, the time to failure being an amount of time for an amplitude of a signal on the medium to degrade beyond a predetermined failure criteria. A time to failure without a stress magnetic field is determined based on the corresponding times to failure determined for each of the different stress currents.

US Patent:

6751039, Jun 15, 2004

Filed:

Nov 3, 2001

Appl. No.:

10/008317

Inventors:

Nelson Shih-Cheng Cheng - Fremont CA
Caleb Kai-Lo Chang - Sunnyvale CA
Steven Lambert - San Jose CA
Tue Thanh Ngo - Milpitas CA

Assignee:

Maxtor Corporation - Longmont CO

International Classification:

G11B 503

US Classification:

360 66, 360 31

Abstract:

A method of controlling bias supply sources for magneto-resistive transducer (MR) heads to provide essentially the same predetermined lifetime for the MR heads, by determining dependence of head lifetime on bias supply level and on head stripe temperature, and setting a bias supply level for each head based on said dependence of lifetime on bias supply level and on head temperature, to provide essentially the same predetermined lifetime for the heads.

US Patent:

7079345, Jul 18, 2006

Filed:

Jan 17, 2002

Appl. No.:

10/054355

Inventors:

Hai Chi Nguy - San Jose CA, US
Steven Lambert - San Jose CA, US
Steven Marshall - Northboro MA, US
George H. Bellesis - Jefferson MA, US

Assignee:

Maxtor Corporation - Longmont CO

International Classification:

G11B 5/09

US Classification:

360 66, 360 55, 360 62, 335209, 335284, 361267, 361143, 361149, 361159

Abstract:

Demagnetizing magnetic media for recording data in a data storage device includes placing the magnetic media in a magnetic field at a first strength, and gradually reducing the magnetic field to a second strength to essentially eliminate net magnetization in the magnetic media.

US Patent:

7924519, Apr 12, 2011

Filed:

Sep 29, 2008

Appl. No.:

12/240139

Inventors:

Steven E. Lambert - San Jose CA, US

Assignee:

WD Media, Inc. - San Jose CA

International Classification:

G11B 27/36

US Classification:

360 31, 360 7704

Abstract:

Monitoring of the eccentricity of a pre-formatted servo pattern on a disk.

US Patent:

8619381, Dec 31, 2013

Filed:

May 25, 2011

Appl. No.:

13/115307

Inventors:

Andreas Moser - San Jose CA, US
Harold H. Gee - San Jose CA, US
Steven E. Lambert - San Jose CA, US
Dragos I. Mircea - San Jose CA, US

Assignee:

WD Media, LLC - San Jose CA

International Classification:

G11B 5/02

US Classification:

360 67, 360 55, 360 75, 360 7706

Abstract:

Systems and methods for improving accuracy of head positioning using existing servo patterns are provided. In one embodiment, a method for improving read head positioning is provided that comprises: writing a series of tracks over a range of read offsets to be calibrated; measuring a set of raw track profiles from the series of tracks; sampling the set of raw track profiles at a series of signal amplitude levels; constructing a reference track profile from the set of sampled track profiles; calculating a set of read offset deltas from each sampled track profile; merging the sets of read offset deltas into a set of average read offset deltas; and converting the set of average read offset deltas into a read offset correction table. A similar method for improving disk write head positioning is also provided which utilizes such a read offset correction table to eventually create write offset correction table.

US Patent:

51494094, Sep 22, 1992

Filed:

Jan 11, 1991

Appl. No.:

7/640182

Inventors:

Richard H. Ahlert - San Jose CA
James K. Howard - Morgan Hill CA
Steven E. Lambert - San Jose CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

C23C 1434

US Classification:

2041922

Abstract:

In the fabrication of thi film cobalt alloy magnetic recording disks by sputter-deposition, the coercivity of the disks can be selectively varied by introducing a predetermined amount of hydrocarbon gas, such as methane, into the argon-based sputtering atmosphere. The flow rate of the hydrocarbon gas into the sputtering chamber is directly related to the coercivity of the resulting disks. This permits the coercivity of the disks to be controlled without the necessity of changing the composition of the cobalt alloy sputtering targets, and without the necessity of changing the thickness of an underlying between the disk substrate and the magnetic layer. The use of hydrocarbon gas in the reactive sputtering of the cobalt alloy magnetic layer in the disks does not affect the intrinsic media noise of the disks, thus allowing for the manufacturing of disks with high signal-to-noise ratio (SNR) of the readback signal.

US Patent:

52065901, Apr 27, 1993

Filed:

Dec 11, 1990

Appl. No.:

7/625343

Inventors:

Bernard Dieny - San Jose CA
Bruce A. Gurney - Santa Clara CA
Steven E. Lambert - San Jose CA
Daniele Mauri - San Jose CA
Stuart S. P. Parkin - San Jose CA
Virgil S. Speriosu - San Jose CA
Dennis R. Wilhoit - Morgan Hill CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G01R 3302
H01L 4308
G11C 1908
G11B 539

US Classification:

324252

Abstract:

A magnetoresistive (MR) sensor comprising a first and a second thin film layer of a magnetic material separated by a thin film layer of a non-magnetic metallic material. The first ferromagnetic layer is magnetically soft. The magnetization direction of the first layer of magnetic material is set substantially perpendicular to the magnetization of the second layer of magnetic material at zero applied field, and the magnetization direction of the second layer of magnetic material is fixed. A current flow is produced through the MR sensor, and the variations in voltage across the MR sensor are sensed due to changes in resistance of the MR sensor produced by rotation of the magnetization in the first layer of magnetic material as a function of the magnetic field being sensed. The variation of the resistance with the angle between the magnetizations of the first and second layers of magnetic material has been defined as the spin valve (SV) effect. It is also shown that, by a suitable direction of the current with respect to the fixed magnetization, the (SV) magnetoresistance can be added constructively to the usual anisotropic magnetoresistance.

US Patent:

63044072, Oct 16, 2001

Filed:

Oct 27, 1998

Appl. No.:

9/182105

Inventors:

Bill Baker - Redwood City CA
Steven Lambert - San Jose CA
Jong Lin - Cupertino CA
Michael Anthony Moser - San Jose CA
Shu-Yu Sun - Saratoga CA

Assignee:

Maxtor Corporation - Longmont CO

International Classification:

G11B 2102

US Classification:

360 75

Abstract:

A coarse magnetic template pattern is transferred to a data storage surface of a disk by magnetic printing techniques. As printed, the template pattern essentially provides clocking and may provide radial position information. The disk is then assembled into a completed and enclosed disk drive. The template pattern is then used by the disk drive to self-write highly resolved product embedded servo patterns onto storage surfaces of each data disk including the surface having the printed template pattern.