公开(公告)号：DE69316099D1

公开(公告)日：1998-02-12

申请号：DE69316099

申请日：1993-05-21

Applicant: IBM

Inventor： LIN TSANN ,  HOWARD JAMES KENT ,  HWANG CHERNGYE ,  MAURI DANIELE ,  STAUD NORBERT

IPC: G11B5/39 ,  G01R33/06

公开(公告)号：DE69534314D1

公开(公告)日：2005-08-25

申请号：DE69534314

申请日：1995-05-02

Applicant: IBM

Inventor： COFFEY KEVIN ROBERT ,  GURNEY BRUCE ALVIN ,  HEIM DAVID EUGENE ,  LEFAKIS HARALAMBOS ,  MAURI DANIELE ,  SPERIOSU VIRGIL SIMON ,  WILHOIT DENNIS RICHARD

IPC: G01R33/09 ,  G11B5/39 ,  G11C11/15 ,  H01F10/08 ,  H01F10/32 ,  H01L43/08 ,  H01L43/10

Abstract: An SVMR sensor (60) having a self-pinned laminated layer (70) with at least two ferromagnetic films (72,74) antiferromagnetically coupled to one another across a thin antiferromagnetically (AF) coupling film (73). Since the two ferromagnetic films (72,74) in this laminated layer (70) have their magnetic moments aligned antiparallel, their two magnetic moments can be made to essentially cancel by making the two ferromagnetic films (72,74) of substantially the same thickness. The magnetic field energy generated by the signal field acting on this laminated layer (70) will be significantly less than the effective anisotropy energy of the laminated layer (70). As a result, the laminated layer (70) will not rotate in the presence of the signal field, but will be "self-pinned". A hard-bias or exchange bias layer in not needed, also eliminating the need for Ni-Mn and its associated high-temperature process.

公开(公告)号：DE69132027T2

公开(公告)日：2000-09-14

申请号：DE69132027

申请日：1991-12-09

Applicant: IBM

Inventor： DIENY BERNARD ,  GURNEY BRUCE ALVIN ,  LAMBERT STEVEN EUGENE ,  MAURI DANIELE ,  PARKIN STUART STEPHEN PAPWORTH ,  SPERIOSU VIRGIL SIMON ,  WILHOIT DENNIS RICHARD

IPC: G01R33/09 ,  G11B5/00 ,  G11B5/39 ,  G01R33/06 ,  H01F10/08

Abstract: A magnetoresistive (MR) sensor is disclosed which comprises 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.

公开(公告)号：IE80856B1

公开(公告)日：1999-04-21

申请号：IE970695

申请日：1997-09-24

Applicant: IBM

Inventor： LEE WEN YAUNG ,  MAURI DANIELE

IPC: G11B5/39 ,  G11B5/40 ,  H01F10/32

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 (Ni89Fe21)60Cr40 and Ni60Cr40. 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 ANGSTROM and 50 ANGSTROM respectively the MR coefficients are optimized. Both spacer layers have a high resistance compatible with low shunting of the sense current.

公开(公告)号：SG53113A1

公开(公告)日：1998-09-28

申请号：SG1997003880

申请日：1997-10-27

Applicant: IBM

Inventor： MAURI DANIELE

IPC: G11B5/00 ,  G11B5/012 ,  G11B5/39

Abstract: A dual spin valve (DSV) magnetoresistive (MR) sensor has a free magnetic layer disposed between first and second pinned magnetic layers. The first pinned layer has two magnetic sublayers separated from each other by an antiparallel spacer. The first magnetic sublayer closer to the free layer has a magnetic moment which is smaller than the magnetic moment of the second magnetic sublayer. The net moment of the magnetic sublayers is chosen to be equal to the magnetic moment of the second pinned layer thus creating a flux closure and substantially minimizing the effect of the demagnetizing forces. By creating a flux closure and current induced magnetic fields, the first and second pinned layers' magnetization are fixed. This is in contrast with conventional dual spin valve sensors using two antiferromagnetic layers to pin the magnetization of the pinned layers.