Wen Wen Lee

Author:

Wen Ho Lee

ISBN #:

0786868031

Author:

Wen Ho Lee

ISBN #:

0786886870

US Patent:

6519120, Feb 11, 2003

Filed:

Aug 2, 2000

Appl. No.:

09/632014

Inventors:

Wen Yaung Lee - San Jose CA
Tsann Lin - Saratoga CA
Daniele Mauri - San Jose CA
Robert John Wilson - Saratoga CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G11B 539

US Classification:

3603241

Abstract:

An SV sensor with the preferred structure Substrate/Seed/Free/Spacer/Pinned/AFM/Cap where the seed layer is a non-magnetic NiâFeâCr or NiâCr film and the AFM layer is preferably NiâMn. The non-magnetic NiâFeâCr seed layer results in improved grain structure in the deposited layers enhancing the GMR coefficients and the thermal stability of the SV sensors. The improved thermal stability enables use of NiâMn with its high blocking temperature and strong pinning field as the AFM layer material without SV sensor performance degradation from the high temperature anneal step needed to develop the desired exchange coupling.

US Patent:

6579590, Jun 17, 2003

Filed:

Nov 16, 2001

Appl. No.:

09/991321

Inventors:

Yongho Ju - San Jose CA
Wen Y. Lee - San Jose CA

Assignee:

Hitachi Global Storage Technologies Netherlands B.V. - Amsterdam

International Classification:

G11B 582

US Classification:

428 653, 428336, 428426, 428457, 428469, 428422, 428694 ST, 428694 TS

Abstract:

A magnetic recording disk for thermally-assisted magnetic recording has a low thermal conductivity multilayered thermal barrier between the substrate and the magnetic recording layer to avoid rapid heat conduction away from the locally heated spot and to reduce the amount of power needed to raise the temperature of the recording media above a required value. The barrier comprises a plurality of alternating layers or bilayers of a metal having an electrical resistivity greater than approximately 100 microOhm-cm and a dielectric selected from the group consisting of oxides, nitrides and oxynitrides of one or more of Al and Si. The large number of metal/dielectric interfaces, each with high thermal resistance, reduces the out-of-plane thermal conductivity of the barrier, and the use of high electrical resistivity metal layers minimizes in-plane heat spreading.

US Patent:

6873499, Mar 29, 2005

Filed:

Jan 24, 2001

Appl. No.:

09/769165

Inventors:

Wen Yaung Lee - San Jose CA, US
Tsann Lin - Saratoga CA, US
Daniele Mauri - San Jose CA, US
David John Seagle - Santa Barbara CA, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G11B005/39

US Classification:

360321

Abstract:

A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe—Hf—O and the Mρ of the flux guide layer is greater than 50 times the Mρ of the read sensor layer where the read sensor layer is NiFe, Mis saturation magnetization and ρ is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.

US Patent:

57319367, Mar 24, 1998

Filed:

Sep 26, 1996

Appl. No.:

8/721642

Inventors:

Wen Yaung Lee - San Jose CA
Daniele Mauri - San Jose CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G11B 539

US Classification:

360113

Abstract:

An MR sensor with an improved MR coefficient and improved thermal stability is provided by employing one or more chromium based spacer layers which are interfacially adjacent a Permalloy (NiFe) stripe. The chromium based spacer layers may be NiFeCr or NiCr. The best compositions have been found to be (Ni. sub. 89 Fe. sub. 21). sub. 60 Cr. sub. 40 and Ni. sub. 60 Cr. sub. 40. For NiCr the MR coefficient of the MR stripe is most enhanced when the NiCr layer is deposited on a layer of tantalum (Ta). Further, when the thicknesses of the NiFeCr and the NiCr layers are 25. ANG. and 50. ANG. respectively the MR coefficients are optimized. Both spacer layers have a high resistance compatible with low shunting of the sense current.

US Patent:

6223420, May 1, 2001

Filed:

Dec 4, 1998

Appl. No.:

9/206016

Inventors:

Wen Yaung Lee - San Jose CA
Tsann Lin - Saratoga CA
Daniele Mauri - San Jose CA
David John Seagle - Santa Barbara CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G11B 542

US Classification:

2960314

Abstract:

A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe--Hf--O and the M. sub. s. rho. of the flux guide layer is greater than 50 times the M. sub. s. rho. of the read sensor layer where the read sensor layer is NiFe, M. sub. s is saturation magnetization and. rho.

US Patent:

45768951, Mar 18, 1986

Filed:

Jun 18, 1984

Appl. No.:

6/621410

Inventors:

Roger W. Barton - Los Altos CA
Hans J. Coufal - San Jose CA
Victor B. Jipson - San Jose CA
Wen Y. Lee - San Jose CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G03C 194

US Classification:

430270

Abstract:

A method of and structure for optical recording by energy-induced homogenization or fractionation is disclosed. When the method involves fractionation, a film is provided that contains a homogeneous mixture of a matrix material and an incident energy absorbing material. A spot on the film is treated with sufficient energy in the form of electric fields, radiation or heat, or combinations thereof to effect fractionation and/or homogenization of the film which will undergo further physical state transition only under treatment with additional energy. In a preferred embodiment, the fractionation is effected by laser radiation. The laser irradiated spot becomes inhomogeneous and can be detected by the resulting changes in its optical properties. When the method involves homogenization, a film is provided that contains a inhomogeneous mixture. The energy treated spot in this case becomes homogeneous without undergoing a phase transition between the amorphous and crystalline phases.

US Patent:

53066987, Apr 26, 1994

Filed:

Oct 10, 1991

Appl. No.:

7/775626

Inventors:

Byung T. Ahn - Seoul, KR
Robert B. Beyers - San Jose CA
Wen Y. Lee - San Jose CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H01L 3924
C01F 1102
C01G 1500

US Classification:

505475

Abstract:

Improved processes for making thin film and bulk thallium superconductors are described, as well as Tl superconductors having high critical current densities and low surface impedance. An annealing step in a reduced oxygen atmosphere is used to convert compounds containing thallium, calcium, barium and copper to a Tl-2223 superconducting phase or to convert an oxide having the nominal composition Tl. sub. 2 Ca. sub. 2 Ba. sub. 2 Cu. sub. 3 O. sub. x to a crystalline Tl-2223 phase. The oxygen pressure during annealing is controlled to be below the thermodynamic stability limit for conversion of Tl-2223 to Tl-2122 and secondary phases. Temperatures less than 880. degree. C. are used, the oxygen pressure being sufficient to prevent excess thallium loss so that the Tl content in the final Tl-2223 phase is Tl. sub. 1. 6-2. Electrical devices including SQUIDs can be made with these improved superconductors.

US Patent:

45325286, Jul 30, 1985

Filed:

May 26, 1983

Appl. No.:

6/498331

Inventors:

Wen Y. Lee - San Jose CA

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G01D 1534

US Classification:

3461351

Abstract:

A recording medium comprising a transport substrate, a tellurium recording layer and an overcoat of selenium from 5 to 60. ANG. thick.