公开(公告)号：JPH104227A

公开(公告)日：1998-01-06

申请号：JP5877797

申请日：1997-03-13

Applicant: IBM

Inventor： GALLAGHER WILLIAM JOSEPH ,  PARKIN STUART STEPHEN PAPWORTH ,  SLONCZEWSKI JOHN CASIMIR ,  JONATHAN ZANHON SAN

IPC: G01R33/06 ,  G01R33/09 ,  G11B5/39 ,  G11C11/14 ,  G11C11/15 ,  G11C11/16 ,  H01L21/8246 ,  H01L27/105 ,  H01L27/22 ,  H01L43/08

Abstract: PROBLEM TO BE SOLVED: To control magnetoresistance response to a magnetic signal by a method wherein a constrained ferromagnetic layer, having a side part circumfer ence which is not extended over the side part circumference of an insulating tunnel layer, is retained within the another spaced plane surface without overlap ping with an insulating tunnel layer. SOLUTION: Write in an MJT is attained by allowing a current to flow through the upper and lower electrode wiring layers on the memory cell application of a magnetic tunnel junction MTJ element. When a sufficiently large current is allowed to flow through the above-mentioned lines, the magnetization direction of a free ferromagnetic layer 32 is rotated in reverse parallel from parallel to the magnetization direction of a constrained ferromagnetic layer 18 by the coupled magnetic field formed in the vicinity of a free ferromagnetic layer 32. Current level is selected in such a manner that the coupling magnetic field to be formed exceeds the switching field of the free ferromagnetic layer. The magnetic field formed by a coupling write-in current is selected smaller than the magnetic field required for rotation of the magnetization direction of the constrained ferromagnetic layer.

公开(公告)号：JPH1012945A

公开(公告)日：1998-01-16

申请号：JP5368997

申请日：1997-03-07

Applicant: IBM

Inventor： JONATHAN ZANHON SAN ,  ARANABA GAPUTA ,  GAN KIANO ,  PHILIP LEWIS SUROOIROUDO ,  PHILIPPE P REKOEA

IPC: G01R33/09 ,  G11B5/33 ,  G11B5/39 ,  G11C11/15 ,  G11C11/16 ,  G11C11/56 ,  H01F10/00 ,  H01F10/08 ,  H01F10/32 ,  H01L43/08 ,  H01L43/10

Abstract: PROBLEM TO BE SOLVED: To provide a three layer thin film reluctance element where a current is transported through a three layer structure by employing an additional perovskite manganate thin film as a ferromagnetic element. SOLUTION: A three layer thin film reluctance element 5 comprises a first or lowermost thin film magnetic layer 2, a second or intermediate layer 3, and a third or uppermost thin film magnetic layer 4, wherein at least one of the first or third layer 2, 4 is an additional manganate perovskite. According to the structure, variation of the reluctance can be substantially doubled in a low field of 150Oe or below close to the saturated coercive force of the element material. Low field spin dependent transportation is achieved in the manganate of the element and the resultant magnitude of magnetoresistance is suitable for a magnetoresistive magnetic field sensor application.